24-hr Uptake Research Articles

Treatment of Graves’ Disease With a Combination of Low Iodine Diet and Potassium Iodide Plus Radioactive Iodine Treatment

Introduction: Graves’ disease (GD) is usually treated with radioactive iodine I131 (RAI), thionamide or surgery. Of these, RAI remains the safest and most efficacious treatment. We report 3 patients with GD who were treated with low iodine diet (LID), followed by RAI and subsequent potassium iodide (SSKI) administration.Case series:Patient 1 - A 50-year-old male presented with weight loss, heat intolerance and palpitations. Physical examination: HR 120 bpm, BP 110/80mmHg, no evidence of thyroid orbitopathy. Thyroid: 50 grams diffusely enlarged and brisk DTR. Lab findings: TSH 0.001, FT4 4.2, total T3 410, TSI 172. A thyroid scan revealed diffuse uptake 72% at 4-hours. He was diagnosed with GD and treated with methimazole. Three weeks later a CBC showed an absolute neutrophil count 820. After discontinuing methimazole, he was placed on prednisone 40mg daily and LID. Two weeks later (24-hours urine iodine <50 mcg), he received 15mCi I131. 72 hours later he was administered SSKI one drop BID for 3 days. Four weeks after RAI, TFT was normal. Two months later, he required levothyroxine treatment for hypothyroidism. Patient 2 - A 23-year-old female presented with weight loss and nervousness. Physical examination revealed HR 110 bpm, BP 100/70 mmHg, no thyroid orbitopathy, a diffusely enlarged thyroid. Serum TSH <0.005, FT4 3.9, total T3 398, TSI 149. Thyroid uptake showed 70% at 24-hours. Patient was started on methimazole and atenolol. Four weeks later she developed severe generalized erythematous rash. After treating with prednisone for one week she was placed on LID and treated with 15 mCi I131. Six weeks later TSH was 0.4 with a free T4 of 1.8 and four months later she required levothyroxine therapy for hypothyroidism. Patient 3 - A 40-year-old male presented with atrial fibrillation and hyperthyroidism. Patient received treatment for atrial fibrillation and physical examination confirmed heart rate 78 (on treatment), no evidence of thyroid orbitopathy, and diffusely enlarged thyroid. Serum TSH <0.005, FT4 3.1, total T3 298, TSI 231. Thyroid scan was consistent with GD with a 24-hr uptake of 62%. He refused to take methimazole due to fear of adverse side effects. After placing him on prednisone along with LID for 2weeks, he was treated with I131 15 mCi. 72 hours later he received SSKI one drop BID for 3 days. Prednisone was discontinued 2 weeks later. Six weeks following treatment, TSH was 1.1 with FT4 1.32. Patient remained euthyroid for the next 12 months of follow up. Discussion: LID given before RAI therapy has a potential of depleting total iodine pool which can increase the I131 uptake in the thyroid gland and facilitate β-radiation to the thyroid gland. SSKI following RAI can improve retention of I131 in the thyroid gland and reduce the recycling of radioactivity between the thyroid and the blood. In summary, a LID prior to RAI and SSKI following RAI treatment be beneficial in certain patients with GD.

Uptake, Disposition, and Persistence of Acrylonitrile in Rainbow Trout

Uptake, Disposition, and Persistence of Acrylonitrile in Rainbow Trout, Lech, J. J., Waddell, W. J., Friedman, M. A., and Johnson, L. R. (1995). Fundam. Appl. Toxicol. 27, 291-294. The uptake and disposition of [2,3- 14C]acrylonitrile-derived 14 C were studied in rainbow trout by water exposure. Trout were exposed to [ 14C]ACN at 5.3 μg/liter and sampled at various times during a 24-hr uptake phase. After transfer to fresh water, fish were sampled to 72 hr for the estimation of elimination rates and the half-life of 14 C. Throughout these experiments several fish were also sacrificed for whole-body autoradiography. The uptake of 14C in carcass and viscera began to level off at 24 hr and the apparent bioconcentration factor was low and of the order of 3-4. In the elimination studies, the 14C appeared to persist in both muscle and visceral tissue for a longer time than anticipated based upon its octanol-water partition coefficient (log p = -0.92). The t 1 2 of 14 C in muscle in two such experiments was calculated to be 117 and 102 hr. The autoradiographs of whole-body sections of exposed trout also revealed a slow loss of 14C from muscle. Muscle extracts prepared from exposed fish were essentially nondialyzable. When dialyzed muscle extract was analyzed for protein and 14C after SDS-PAGE electrophoresis, most of the 14C was associated with a single protein band with a mobility comparable to standards in the 10,000 Dalton range. These studies indicate that the long half-life of 14C seen in trout muscle may be due to covalent binding of 14C to a protein with a molecular weight of approximately 10,000 Daltons.

Uptake, Disposition, and Persistence of Acrylonitrile in Rainbow Trout

The uptake and disposition of [2,3-14C]acrylonitrile-derived 14C were studied in rainbow trout by water exposure. Trout were exposed to [14C]ACN at 5.3 μg/liter and sampled at various times during a 24-hr uptake phase. After transfer to fresh water, fish were sampled to 72 hr for the estimation of elimination rates and the half-life of 14C. Throughout these experiments several fish were also sacrificed for whole-body autoradiography. The uptake of 14C in carcass and viscera began to level off at 24 hr and the apparent bioconcentration factor was low and of the order of 3–4. In the elimination studies, the 14C appeared to persist in both muscle and visceral tissue for a longer time than anticipated based upon its octanol-water partition coefficient (log p = −0.92). The t½ of 14C in muscle in two such experiments was calculated to be 117 and 102 hr. The autoradiographs of whole-body sections of exposed trout also revealed a slow loss of 14C from muscle. Muscle extracts prepared from exposed fish were essentially nondialyzable. When dialyzed muscle extract was analyzed for protein and 14C after SDS-PAGE electrophoresis, most of the 14C was associated with a single protein band with a mobility comparable to standards in the 10,000 Dalton range. These studies indicate that the long half-life of 14C seen in trout muscle may be due to covalent binding of 14C to a protein with a molecular weight of approximately 10,000 Daltons.

EFFECT OF SURFACTANTS ON UPTAKE OF GIBBERELLIN A3 BY SOUR CHERRY LEAVES

Gibberellin A3 (GA) applied to virus-infected sour cherry (Prunus cerasus L., `Montmorency') trees inhibits flower initiation and promotes spur formation. However, response to a given dose may vary. Differential foliar absorption has been suggested as a major source of this variation. Therefore, we studied if surfactants would reduce variation in GA absorption. Uptake through the abaxial surface exceeded that through the adaxial surface by about one order of magnitude (adaxial surface 1.1 vs 7.8% in 1988, 0.7 vs 16.6% in 1989). GA uptake was markedly affected by surfactants. Over a 24-hr uptake period, Activator 90 and Ortho X-77 were most effective (abaxial surface 38.3 and 37.4% in 1989), whereas Regulaid did not affect GA uptake. L-77 significantly depressed absorption (abaxial surface 9.1% in 1989). In addition to the level of uptake, surfactants also changed GA absorption kinetics. Penetration increased linearly over a 96-hr time period when Regulaid was included. However, with Ortho X-77, uptake was rapid initially but levelled off within 96 hr. These findings will be discussed in relation to biological response data obtained in the field experiments.

An epidemiological study of subacute thyroiditis in northern Japan

It is difficult to study subacute thyroiditis epidemiologically since it occurs sporadically and infrequently. Information about 1,127 cases (108 males, 1,019 females, from 1967 to 1982) of subacute thyroiditis in northern Japan was obtained through a questionnaire. It was found that the usual age for the disease was forty, that females predominated in a ratio of 10.6:1, and that the prevalent month was July. In clinical features, the frequencies of the inflammatory symptoms were high in the acute phase of the disease, and the frequencies of hyperthyroid symptoms increased with the progress of the disease. According to the course of the disease (days after the onset without treatment), the patients were divided into seven subgroups, such as 1 approximately 7 days, 8 approximately 14 days, 15 approximately 21 days, 22 approximately 28 days, 29 approximately 42 days, 43 approximately 56 days and over 57 days, respectively. Compared with the 1 approximately 7 days group, the erythrocyte sedimentation rate, serum T4 and T3 concentrations in the 15 approximately 21 days group showed a significant increase from 64 +/- 35 to 75 +/- 30 mm/h (p less than 0.001), 14.6 +/- 5.5 to 17.6 +/- 5.6 micrograms/100 ml (p less than 0.001) and 218 +/- 124 to 263 +/- 109 ng/100 ml (p less than 0.05), respectively, but the BMR showed as insignificant increase from 20 +/- 15 to 24 +/- 14%. The 24-hr 131I-thyroid uptake and resin sponge uptake (RSU) in the 21 approximately 28 days group were 1.2 +/- 1.5% and 35.1 +/- 6.7%, respectively; the former was significantly lower (p less than 0.02) and the latter was insignificantly higher than the values (2.0 +/- 2.6% and 33.9 +/- 7.9%, respectively) in the 1 approximately 7 days group. The recovery time in the steroid-treated group was 57.2 +/- 47.6 days, which showed a statistically insignificant difference from 64.8 +/- 50.5 days of the sodium salicylate-treated group. But the recovery time of 78.2 +/- 64.9 days in other anti-inflammatory drug-treated groups was significantly longer than that of the steroid and sodium salicylate-treated groups (p less than 0.001 and p less than 0.05). Among 9 viral diseases, such as measles, varicella, erythema infection, hand-foot and mouth disease, rubella, mumps, influenza, epidemic keratoconjunctivitis and acute hemorrhagic conjunctivitis observed in northern Japan and Miyagi prefecture in the past 4 years, mumps, hand-foot and mouth disease and epidemic keratoconjunctivitis were prevalent in summer.(ABSTRACT TRUNCATED AT 400 WORDS)

Low thyroid uptake of radioiodine

A 57-yr-old woman was evaluated because of a 3-too history of hoarseness. Mirror laryngoscopy revealed some atypical masses at the base of the tongue. In 1944 she had a tissue biopsy from this area and she was told this was a thyroglossal duct remnant. Nothing further was done until the present time. A 24-hr radioactive iodine uptake was performed after the oral administration of 5 uCi of ~3JI. With the probe in the usual position over the thyroid cartilage, the uptakes were low and were essentially the same as the thigh counts. With the probe centered over the base of the tongue, the 24-hr uptake was 6%. Thyroid scans performed with 99mTC and a

Cold nodule—Thyroid scan

T HIS 70-yr-old female was referred for thyroid scanning because of a mass in her neck of increasing size over a 2-yr period. Physical exam revealed 3 x 4 cm mass in the right lower pole. A 2-hr and 24-hr uptake was obtained after the oral administration of 112.5 uCi of 123I. The 2-hr uptake was 4% and 24-hr uptake was 17% both of which are within normal limits. The thyroid scan demonstrated an asymmetric thyroid gland, with the right lobe of thyroid displaced medially by a large cold nodule that measured 3.5 x 5 cm on the scan (Fig. 1). Ultrasound revealed this mass to be solid. The patient underwent surgery, and pathology revealed follicular adenoma.

The Use of Ferrokinetics in the Study of Experimental Anemia

Erythropoietic cells in bone marrow are vulnerable to cytotoxic substances. There are three types of erythroid precursors: cells that can take up Fe but do not proliferate (reticulocytes), those that can take up Fe and proliferate (normoblasts and pronormoblasts), and those cells that do not take up Fe but can proliferate and differentiate into the erythroid cell line (ERC and stem cells). Each of these erythroid precursors requires a certain time before they emerge into the peripheral blood as mature red blood cells. By applying our understanding of ferrokinetics associated with erythropoiesis, it was possible to estimate a cytotoxic effect of chemicals on proliferating erythgroid precursors (pronormoblasts) in mice by measuring 24-hr 59Fe uptake in red blood cells 48 hr after treatment with chemicals. The effect of chemicals on pluripotent hemopoietic stem cells in mice was also estimated by measuring 24-hr 59Fe uptake 72 hr after treatment with chemicals. The validity of experimental schemes was tested using cytarabine, methotrexate, vinblastine, cyclophosphamide, and busulfan, which are known to act against specific cell types. Effects on pluripotent hemopoietic stem cells were tested with or without activation of stem cells in G0 into cell cycle. Applications of the 59Fe uptake method in the study of (1) benzene toxicity and (2) effect of pentobarbital on the toxic action of hydroxyurea and cytarabine are described. Proper application of the ferrokinetic characteristics of erythropoietic cells enables the establishment of a methodology which can be used to evaluate potential toxic effects of chemicals on erythroid precursor cells and pluripotent hemopoietic stem cells.

The use of ferrokinetics in the study of experimental anemia.

Erythropoietic cells in bone marrow are vulnerable to cytotoxic substances. There are three types of erythroid precursors: cells that can take up Fe but do not proliferate (reticulocytes), those that can take up Fe and proliferate (normoblasts and pronormoblasts), and those cells that do not take up Fe but can proliferate and differentiate into the erythroid cell line (ERC and stem cells). Each of these erythroid precursors requires a certain time before they emerge into the peripheral blood as mature red blood cells. By applying our understanding of ferrokinetics associated with erythropoiesis, it was possible to estimate a cytotoxic effect of chemicals on proliferating erythgroid precursors (pronormoblasts) in mice by measuring 24-hr 59Fe uptake in red blood cells 48 hr after treatment with chemicals. The effect of chemicals on pluripotent hemopoietic stem cells in mice was also estimated by measuring 24-hr 59Fe uptake 72 hr after treatment with chemicals. The validity of experimental schemes was tested using cytarabine, methotrexate, vinblastine, cyclophosphamide, and busulfan, which are known to act against specific cell types. Effects on pluripotent hemopoietic stem cells were tested with or without activation of stem cells in G0 into cell cycle. Applications of the 59Fe uptake method in the study of (1) benzene toxicity and (2) effect of pentobarbital on the toxic action of hydroxyurea and cytarabine are described. Proper application of the ferrokinetic characteristics of erythropoietic cells enables the establishment of a methodology which can be used to evaluate potential toxic effects of chemicals on erythroid precursor cells and pluripotent hemopoietic stem cells.

Plasma dopamine-beta-hydroxylase activity and thyroid suppressibility in Graves' disease

Plasma dopamine-beta-hydroxylase (DBH) activity, serum T4, T3, T3U, and the 24-hr thyroid uptake before triiodothyronine suppression testing were studied in 34 patients with treated Graves' disease. Although all of them were in the euthyroid state, there was a statistically significant difference in presuppression plasma DBH activity between those patients who showed suppression of their RAI uptake with triiodothyronine and those who did not. This suggests a relationship between plasma DBH activity and thyroid suppressibility.

The effect of dietary ingestion of oxalic acid on thyroid function in male and female Long-Evans rats

Male and female Long-Evans rats revealed decreased body weights and restricted growth rates when placed on a diet of Purina laboratory chow which was supplemented with 2.5 and 5.0% oxalic acid for a period of 70 days. Male and female rats ingesting 5.0% oxalic acid in the diet showed severe losses in body weight. Significant reduction in thyroid weight, 24-hr thyroid uptake of 125I, and plasma radioactivity were observed together with a significant increase in plasma thyroid-stimulating hormone in male and female rats ingesting dietary 5.0% oxalic acid. Chromatographic analysis of thyroid hydrolysates revealed an increase in thyroid labeling of monoiodotyrosine (MIT) which was associated with a decrease in labeling of diiodotyrosine (DIT) leading to elevation in MIT : DIT ratios. While the labeling of tetraiodothyronine (T 4) was unaffected, a significant increase in triiodothyronine (T 3) resulted in elevation of the T 3 : T 4 ratios. These results indicate that chronic ingestion of oxalic acid at the level of 5.0% can lead to a state of hypothyroidism.

STUDIES ON T3 SUPPRESSION TEST IN THYROTOXIC PATIENTS RECEIVING ANTITHYROID DRUGS

It is known that 24-hr uptake, not 20-min uptake, is affected by thionamide drugs during thyroid suppression test (ST). On the other hand, previous studies have shown that 24-hr uptake could be used for the ST in patients with thyrotoxicosis receiving thionamide drugs. However, little information is available on the comparison of the effect of antithyroid drugs in the ST by 24-hr uptake.Forty-seven patients were treated with propylthiouracil (PTU, 50-100mg>/day) or methylmercaptoimidazole (MMI, 5-10mg/day) in a maintenance dose for 1-4 years since they became euthyroid (serum TSH : within normal limits). All patients had PTU or MMI even on the day of the measurement of 131I-thyroid uptake (24-hr, %, Up). The first ST was performed : 75μg T3 daily for 8 days given and Up determined. The second ST was assessed on the same patients 4 weeks after either changing PTU into MMI or MMI into PTU. Most of the patients showed a marked depression of post T3 Up during MMI therapy compared to values of PTU therapy. There was no significant difference between the two antithyroid drug treatment in the serum T4, T3 and TSH levels before and after T3 administration. Twenty-five patients showed Up below 35% after T3-ST, regardless of PTU or MMI treatment. Of these 20 remained euthyroid and 5 relapsed within 2 years after withdrawal of antithyroid drugs. The mean post T3 Up in remission was : MMI 4.6±0.7% ; PTU 18.4±3.2%. In contrast, the mean post T3 Up in relapse was : MMI 11.1±3.1% ; PTU 32.1±10.0%.Conclusively, the present study lend to the proposal that criteria of ST by 24-hr Up should be considerd by antithyroid drugs used : MMI less than 5%, PTU less than 20% in the post T3 Up. MMI is more than 10 times effective in depressing the post T3 Up compared to PTU.

Event-related slow potential (ERSP) correlates of thyroid gland function level.

This study shows an association between thyroid gland function level and event-related slow brain potential (ERSP) parameters (peak amplitude and area under the curve), obtained during "classical" and "operant" reaction-time paradigms. A significant positive correlation between ERSP parameters and 24-hr I131 uptake and a negative nonsignificant one between them and ankle jerk reflex were found. Organismic factors related to thyroid function had greater influence upon ERSP amplitude and area than situational ones, for no significant effect of task was evidenced and no interaction between them was found under the conditions employed. Hyper- and hypothyroids showed also a tendency to present longer reaction times than euthyroids. These results are discussed within the framework of the arousal-distraction coupling hypothesis as proposed by Tecce and Cole (1976) and compared to those previously obtained in high-neuroticism anxiety-prone indivuduals. Although these and hyperthyroids do show indications of similar behavioral manifestations (excessive reactive arousal), both groups are considered to differ regarding empirical referennts of anticipatory arousal (ERSP parameters). A major difference seems to be the absence of a "ceiling effect" in hyperthyroids. This hypothetical phenomenon can be expected on the basis of the inverted U-shaped relation between ERSP amplitude and arousal level. A stronger "distraction" effect associated with increased arousal in anxiety neurotics is postulated and tentatively attributed to covert verbalizations of worry and feelings added to increased awareness of autonomic input. The contention is advanced that similar behavioral manifestations could be distinguishable at the physiological level employed and this might add further insights to diagnostic typologies (e.g., "psychosomatic" vs. "psychoneurotic" patients).

TRH and T3 suppression tests after 131I therapy of thyrotoxicosis (author's transl)

TRH and T3 suppression tests were performed on patients (124 cases) with Graves' disease who underwent radiation therapy. TRH test was performed at 4-6 months (Group I), 6-12 months (Group II), 12-24 months (Group III) and 24-50 months (Group IV) after final radiation therapy, and T3 suppression test was performed just after each TRH test. The response to TRH test was defined as positive when the basal TSH value was less than 2.0 muU/ml and the peak value was more than 6.2 muU/ml following TRH (500 mug) injection. T3 suppression test was performed by measuring the 24-hr thyroidal uptake of radioiodine after daily administration of 75 mug of T3 for 8 days. The response was defined as positive when the value for 24-hr uptake after T3 administration was less than half of the control value. The results were as follows; 1) Among 124 patients in Group I to IV who were clinically euthyroid and whose T3-RU and T4 values were normal, compared with other groups, Group IV (2-4.2Y) showed a significantly higher percentage of positive responses to both TRH and T3 suppression tests. However, among 49 of 124 patients whose T3 was also normal, there were no significant differences between the groups. 2) The value of triiodothyronine was above the normal range in many cases up to 2 years after radiation therapy (in Group I, II, III). 3) There were no significant differences in the percentage of hyperresponses between any of the four groups. Half of the patients who showed positive responses to TRH test showed exaggerated responses. 4) In all cases when the responses to TRH and T3 suppression tests changed from negative to positive, thyroxine and triiodothyronine concentrations must be within the normal range. In particular, the major determinant seems to be the value of triiodothyronine. 5) As in more than 30% of cases TRH and T3 supression tests changed from negative to positive, thyroxine and triiodothyronine concentrations must be within the normal range. In particular, the major determinant seems to be the value of triiodothyronine. 5) As in more than 30% of cases TRH and T3 suppression tests remained negative even though their T3-RU, T4, T3, values became normal after radiation therapy, the regulation of hypothalamo-hypophyseal thyroid axis do not always return to normal even though circulating thyroidal hormone level return to an euthyroid state.

Changes in responsivity to TRH test and T3-suppression test after surgical treatment of hyperthyroidism (author's transl)

TRH test and T3 suppression test were performed on patients with Graves' disease who underwent subtotal thyroidectomy after treatment with antithyroid drugs for 2.5 approximately 5 months. On 43 or the patients, TRH test was performed before, 1 week after and 1 approximately 2 months after surgery and T3 suppression test was also performed in 1 approximately 2 months post-operative period. For other 3 groups of the patients TRH test was performed at 2 approximatley 6 months, 6 approximately 12 months, 12 approximately 24 months and 24 approximately 41 months after surgery, and T3 suppression test was also performed just after each TRH test. As to TRH test, the response was defined as positive when basal TSH value was less than 2.0 muU/ml and peak value was more than 6.2 muU/ml or the difference between basal TSH and peak TSH value was over 5 muU/ml following TRH (500 mug) injection. T3 suppression test was perfomed by measuring the 24-hr thyroidal uptake of radioiodine after daily administration of 75 mug of T3 for 8 days. The response was defined as positive when the value for 24-hr uptake after T3 administration was less than half of the control value. The results were as follows; (1) In 11 of 43 patients, response to TRH test already changed to positive 1 week after operation and in 21 of 43 patients TRH test changes to positive 1 approximately 2 months after operation. (2) In general, response to TRH test changed to positive earlier than response to T3 suppression test. (3) T3 suppression test in 1 approximately 2 months after operation was useful to evaluate prognosis. (4) A half of the positive respondents to TRH test showed exaggerated response. (5) Basal TSH value of positive respondents to TRH test was 9.27 +/- 1.81 muU/ml (mean +/- SE) which exceeded the normal range. (6) Some patients showed negative response to conventional T3 suppression test despite of their high basal TSH value. This might be due to the insufficient dose of T3 to suppress TSH. (7) Concerning patients whose serum T3-RU, T4, T3 and TSH were within normal limit after subtotal thyroidectomy, 80% of them showed correspondance in the results of TRH test and T3 suppression test.

Radioiron utilization and ethylenediamine in female mice

The effects of ethylenediamine (EDA) on the distribution of radioiron citrate ( 59Fe) among erythrocytes, plasma, spleen, and liver were explored in female ICR mice. The 7-day LD50 of EDA was found to be 1.5 mg/g sc. Within hours of injection a maximum nonlethal dosage of EDA appeared to reduce the availability of 59Fe for erythropoiesis. A more prolonged effect was also observed where EDA reduced the erythrocyte 24-hr 59Fe uptake during a 1-week period following administration. Spleen 59Fe uptake was affected by EDA most during the early period; a dose-response relationship was noted. Liver and femur obtained from experimental animals did not vary in their 59Fe content from those of control mice at all test intervals. The hematocrit and total hemoglobin were not changed by EDA treatment.

Kinetics of thyroxine and triiodothyronine in a case of thyroxine-binding globulin deficiency with hypothyroidism.

Kinetics of T3 and T4 were studied in a case of TBG deficiency with hypothyroidism. Serum total and free T4 of 35-year-old man were 0.6 μg/100ml and 0.54 ng/100ml, respectively. Serum total and free T3 were 18 ng/100ml and 74 pg/100ml, respectively. BMR was -27%. Thyroidal 24-hr uptake of 131I was 7%. Resin-sponge 131I-T3 uptake was 52%. Binding capacity of TBG was O. Binding capacities of TBPA measured by two different methods were 240 and 223 μg/100ml. The half-life of T4 was shortened, the T4 distribution space, turnover rate and clearance rate increased. Extrathyroidal organic iodine pool and degradation rate decreased. The half-life of T3 was slightly shortened, turnover rate, distribution space and clearance rate increased. Extrathyroidal T3 pool and degradation rate decreased. During the treatment with 75 μg/day of l-T3, the patient's complaints disappeared. When administration of l-T3 was switched to 400 μg/day of l-T4, elevated serum T3 remained higher than the preadministration level. His mother and a younger sister had decreased T4-binding capacity of TBG.

Juvenile chronic lymphocytic thyroiditis: clinical, laboratory and histological correlations.

ABSTRACT Thirty-two children with histologically proven chronic lymphocytic thyroiditis were assessed for clinical, laboratory and histological correlations. An inverse relationship between radioimmunoassayable thyroid-stimulating hormone (TSH) and serum thyroxine by column (T4), and TSH and free thyroxine (FT4) was demonstrated. Significant correlations were noted between TSH levels and thyroid tanned red cell hemagglutination antibodies (χ2=4.78, p <0.05), and unfixed Coons antibody titers (χ2=13.26, p <0.005). Abnormal radioactive iodine uptakes were found in 11 of 22 patients examined. A statistically significant linear correlation between the 4-hr uptake and log serum TSH was shown (γ=0.683, p <0.01), while the 24-hr uptake had no correlation. Utilizing the relation between TSH and T4, and TSH and thyroid antibody titers, 18 of 19 patients with elevated TSH levels could be predicted by the selected criteria of a T4 <4.0 μg/100 ml or an agglutinating titer⋝1: 256 or a Coons fluorescent antibody titer⋝...

Presence and distribution of gonadotropin and thyrotropin in the pars distalis of the lizard Anolis carolinensis

Partial hypophysectomy and bioassay of pituitary extracts were used to study the presence and distribution of thyrotropin (TSH) and gonadotropin within the pars distalis of the adult male lizard ( Anolis carolinensis). Removal of different regions of the pars distalis indicated that gonadotropin was produced throughout the gland, whereas TSH was produced primarily by the caudal region of the gland. Injections of extracts of either rostral or caudal halves of the pars distalis stimulated testicular growth and interstitial cell activity in hypophysectomized Anolis, and the concentration of gonadotropin appears to be approximately equal in the two regions. The existence of two separate gonadotropins in reptiles is questioned. Hypophysectomy produced a gradual decline in the rate of radioiodine uptake by the thyroid; 24-hr uptake values 11 days after hypophysectomy were only 20% of control values, and after 21 days they were only about 2% of controls. A reduced rate of urinary 131I excretion also occurred in hypophysectomized animals. Chromatographic analysis of hydrolyzed thyroid homogenates and plasma indicated a relatively high rate of T 4 production and secretion by the thyroids of intact animals, suggesting that the reptilian thyroid is not as sluggish as previously described. Hypophysectomy significantly reduced the rate of thyroid hormone biosynthesis. Only the caudal half of the pars distalis appeared to have TSH activity as judged by the radioiodine uptake and labeling of T 4 in hypophysectomized Anolis injected with pituitary extracts. Animals injected with caudal tissue also showed significantly more lean growth than the other hypophysectomized animals. These results are discussed in relation to histological studies of pituitary cell types. Previous identification of pituitary thyrotropes and gonadotropes appear incorrect and a tentative scheme for the functional identification of the 5 recognized cell types in the pars distalis is proposed in light of recent bioassays of the pituitary hormones in reptiles.

The TSH Test in Persons Having Received Iodine Compounds

SummaryThe 2-hr 132I thyroid uptake was measured serially in 5 groups of normal volunteers whereas the 2-hr and the 24-hr uptake of 131I were measured in a sixth group. Following administration of potassium iodide in doses of 40, 200 and 1000 mg, Urografin or Biligrafin i.v., the thyroid uptake decreased to very low values. A single injection thereafter of 10 I.U. of TSH increased these low values to levels within the normal range. A direct assessment of the individual level of thyroid function cannot be obtained by the described procedure because of lack of linear correlation between the values obtained for the PII and the uptake measurements after TSH administration. It is concluded that TSH can be used for differentiating low uptake values due to primary hypothyroidism from those after iodine ingestion in either inorganic or organic form. In such patients, TSH may also help in obtaining a better scintigram of the thyroid gland.