Indicator Fractionation Technique Research Articles

Capillary blood flow in the genital tracts of conscious ewes: cyclic changes and the effect of ovarian hormones.

The indicator fractionation technique with [86Rb]rubidium chloride as the indicator was used in conscious animals to determine the relative blood flow (RBF) as a measure of capillary blood flow in regions of the genital tract of cyclic ewes and of hormonally treated ovariectomized ewes. The RBF values in the ampulla, isthmus, uterus and cervix of cyclic ewes were markedly raised at pro-oestrus and declined thereafter to low levels during the remainder of the oestrous cycle. On Day 4 a small secondary rise in flow occurred in the ampulla and isthmus. In ovariectomized ewes, oestradiol induced high levels of RBF in the ampulla, isthmus, uterus and cervix whether the animals had been treated previously with progesterone or given concurrent small doses of progesterone. Though progesterone given alone caused a significant rise in RBF in the uterus, this effect appeared to be one occurring only during active re-growth of regressed tracts. The findings are discussed in relation to oestradiol inducing a stimulatory effect on RBF in the genital tract of the ewe around oestrus but not at Days 3-4 of the oestrous cycle.

Intestinal blood flow in the dog measured by indicator fractionation without tissue samples.

1. A modification of Sapirstein's indicator fractionation technique for measurement of intestinal blood flow has been studied and evaluated in the dog. 2. The concentration of 42K within the intestinal wall was measured simultaneously by a tissue assay procedure and by use of a miniature Geiger-Müller tube within the intestinal lumen. Both methods gave similar results under a wide variety of conditions. 3. Isotope measurement by the Geiger-Müller tube technique obviates the need for tissue samples to be taken and would permit repeat measurements of intestinal blood flow in the same animal.

Measurement of placental blood flow in the pig and its relation to placental and fetal weight.

In 12 pregnant sows (Sus scrofa domestica), containing 144 live fetuses, placental blood flow was measured by the indicator fractionation technique using radioactive microspheres. In 8 of these litters, which contained 96 live fetuses, placental blood flow as obtained in absolute units. Significant positive correlations were observed between placental blood flow and placental weight, between placental blood flow and fetal weight, and between placental weight and fetal weight. It is clear that the runt, by comparison with his littermates, has a low birthweight in association with a small placenta and a low placental blood flow.

Effect of Fasting on Mucosal Blood Flow in Antrum and Corpus of the Stomach

Gastric mucosal blood flow in the rat was determined by the indicator fractionation technique 86RbCl. Antral and corpus flow rates were determined after increasing periods of fasting, and the effect of vagotomy was assessed. The physiological stimulus of food in the stomach markedly increased antral as well as corpus blood flow, and after vagotomy lower flow rates were recorded in all parts of the stomach. With progressive starvation, the antral:corpus flow ratio decreased. The findings suggest that the antrum plays an active role in response to a physiological stimulus and may, as has been suggested by others, contribute to the control of parietal cell blood flow and secretion.

Circulation in rats with Guérin carcinoma.

After implantation of Guérin carcinoma in rats, cardiac output (by Evans-blue dilution), distribution of the organ fractions of cardiac output (by Sapirsteins's isotope indicator fractionation technique), nutritive blood flow and circulatory resistance of the organs (including the tumor) were studied. The following parameters were altered proportionately to the weight of the tumor (0.39-84.0 g): a) weight of gut and carcass diminished; b) cardiac index increased, blood pressure and total peripheral resistance decreased; c) tumor fraction of cardiac output was augmented; d) blood flow of the organs increased and their circulatory resistance decreased. Hematocrit decreased from 47.2 to 31.0% 20 days after tumor implantation. In rats with tumor the changes of blood flow may be conditioned by both anemia and the decrease in organ weight.

Cerebral fluid dynamics and brain regional blood flow in experimental hydrocephalus.

Cerebral blood flow was measured by the indicator fractionation technique in normal, acute hydrocephalic, chronic compensated hydrocephalic and craniectomized hydrocephalic cats. In the five normal cats the mean total brain blood flow was 136.1 ml/min/100 g dry weight. The six acute hydrocephalic animals demonstrated a relatively uniform 22% reduction in total blood flow. In eight chronic hydrocephalic cats CBF increased to the point where there was only an overall 7% decrease. In three hydrocephalic and craniectomized cats the CBF was reduced by 30.6%. In the acute phases there was a decrease in the number of blood vessels. Chronic compensated hydrocephalic brains had somewhat more vessels than the normal, whereas the craniectomized, massively hydrocephalic brain had a dramatic increase in both the number and caliber of blood vessels. These results clearly demonstrate that in acute obstructive hydrocephalus in cats, there is a significant decrease in CBF. The blood vessels revert to normal in shunted cats.

Effect of Lactose Content and Milking Interval on Mammary Blood Flow1,2

Eighteen primiparous mice in their 6th to 9th day of lactation were randomly divided into groups of six. Each group was assigned to one of the three milking intervals, .25, 4, and 12h. Blood flow was measured simultaneously in right and left abdominal mammary glands by Sapirstein's indicator fractionation technique with sodium24 chloride as the indicator. Lactose was extracted from the same tissue and quantified by gas chromatography.Up to 4h, mammary blood flow was inversely related to the amount of milk accumulated in mammary gland. Around 4h blood flow started to level off and somewhere between 4 and 12h reached a maintenance rate. Rate of lactose synthesis was markedly reduced in this period. The relationship between mammary blood flow (Y) and lactose content (X) in the tissue was curvilinear, Y = 4.43 − .83X + .06X2 (correlation – .83).

Regional Distribution of Feline Esophageal Blood Flow

The regional distribution of esophageal blood flow has not been studied in man or in an animal whose esophageal musculature is histologically similar. The cat is the only common laboratory animal whose esophagus, like man’s, contains both striated and smooth muscle in the muscularis externa. Nutrient blood flow to sequential mucosal and muscular segments of the feline esophagus was determined by use of the indicator fractionation technique and cardiac output studies. The smooth muscle of the muscularis externa received a slightly higher flow (21 ml per min per 100 g) than did striated muscle (17 ml per min per 100 g). This relative similarity of nutrient flow to these histologically different muscle types may reflect that they function in concert in the esophagus and are under similar neural control. Blood flow to 1 gram of esophageal mucosa and muscularis externa was similar. This distribution differs from that reported for the stomach and small bowel where 1 gram of mucosa receives a greater nutrient flow than does the muscularis externa. These distribution differences reflect functional and morphological differences between these parts of the gastrointestinal tract.

Regional Distribution of Feline Esophageal Blood Flow

The regional distribution of esophageal blood flow has not been studied in man or in an animal whose esophageal musculature is histologically similar. The cat is the only common laboratory animal whose esophagus, like man’s, contains both striated and smooth muscle in the muscularis externa. Nutrient blood flow to sequential mucosal and muscular segments of the feline esophagus was determined by use of the indicator fractionation technique and cardiac output studies. The smooth muscle of the muscularis externa received a slightly higher flow (21 ml per min per 100 g) than did striated muscle (17 ml per min per 100 g). This relative similarity of nutrient flow to these histologically different muscle types may reflect that they function in concert in the esophagus and are under similar neural control. Blood flow to 1 gram of esophageal mucosa and muscularis externa was similar. This distribution differs from that reported for the stomach and small bowel where 1 gram of mucosa receives a greater nutrient flow than does the muscularis externa. These distribution differences reflect functional and morphological differences between these parts of the gastrointestinal tract.

Salt‐gland secretion and blood flow in the goose

1. Salt-gland blood flow in the domestic goose has been measured using a combination of Sapirstein's indicator fractionation technique for organ blood flow and Fegler's thermodilution method for cardiac output.2. Nasal salt secretion was induced by giving 0.5 M-NaCl or 0.154 M-NaCl I.V. or by giving artificial sea water by stomach tube into the proventriculus.3. During secretion, salt-gland blood flow increased from 82.7 +/- 21.9 ml./100 g tissue. min to as high as 2179 ml./100 g. min (mean 1209 +/- 140).4. The rate of secretion in response to salt loading was very variable and was not correlated with the rate of blood flow.5. From the data obtained, it could be calculated that the median values for the percentage extraction of ions from the arterial plasma were Na 15%, K 35%, Cl 21% and water 5.8%.6. Atropine abolished secretion but not the increase in blood flow produced by salt loading.7. Unilateral complete denervation abolished secretion from and the increase in blood flow through the operated but not the control gland.8. Anaesthesia, induced by pentobarbitone sodium, almost completely blocked secretion and the increase in blood flow in the salt-gland in response to salt loading.9. In geese given 0.5 or 0.154 M-NaCl I.V. a positive, significant correlation was found between the total amount of nasal secretion collected over 30 min and the concentrations of Na and Cl in the nasal fluid. However, when the time course of secretion was followed in any one bird, the rate of secretion was inversely related to the concentrations of Na and Cl.10. Harderian gland blood flow was not affected by salt loading.

Changes in the permeability of the testicular capillaries and of the 'blood-testis barrier' after injection of cadmium chloride in the rat.

SUMMARY Blood flow, capillary permeability and the entry of rubidium into the testis, epididymis, skeletal muscle and brain of male rats were examined within 6 hr. of giving an s.c. injection of cadmium chloride (3 μmole/100g. body wt). Sapirstein's (1958) indicator fractionation technique was used to measure blood flow with [125I]iodoantipyrine and simultaneously capillary permeability and rubidium uptake were assessed using 131I-labelled human serum albumin and [86Rb]rubidium chloride respectively. Blood flow in the testis and the initial segment of the caput of the epididymis increased in the first 2 hr. after cadmium administration, returned to control levels at 3 hr., and thereafter sharply decreased. Labelled albumin began to accumulate in extravascular compartments 3–4 hr. after cadmium; in the head of the epididymis this increase in capillary permeability appeared earlier than in the testis and preceded the fall of blood flow. The limited transport of rubidium into the seminiferous tubules was again observed and used as a criterion of tubular integrity. The uptake of 86Rb by the testis increased within 2 hr. of giving cadmium and thus preceded the extravascular transport of albumin from the capillaries. This is the earliest indication of cadmium damage to the tubules so far reported. There were no systematic changes in these parameters in the rest of the epididymis, skeletal muscle or brain.

Relationship between pancreatic secretion and pancreatic blood flow.

An indicator fractionation technique using radioactive rubidium has been used to measure pancreatic blood flow after infusions of secretin, pancreozymin, urecholine, and pentagastrin. Secretin resulted in the production of a large volume of low viscous pancreatic juice and was associated with an increase in the cardiac output. Duodenal and pancreatic blood flow and perfusion rate were increased significantly. Blood flow to the remainder of the gastrointestinal organs was only marginally increased but the perfusion rate in each organ was increased significantly.Infusion of pancreozymin, urecholine, and pentagastrin resulted in the output of a small volume of viscous juice and was associated with no increase in cardiac output but with an increase in both pancreatic blood flow and perfusion rate.

The tudy of the cerebral circulation in Scandinavia.

Proceedings of the British Institute of RadiologyPublished Online:29 May 2014https://doi.org/10.1259/0007-1285-42-500-637SectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail AboutAbstractThere are a number of indicator dilution or indicator fractionation techniques which are applicable to the measurement of cerebral blood flow (CBF). These methods and their underlying principles have been reviewed briefly elsewhere (Veall, 1968). A number of important techniques exist which are not covered in detail in the present Symposium; of particular importance is the Kety-Schmidt method (1948), partly for historical reasons and partly because it is the method which has to be employed for cerebral metabolic studies. The same workers were the first to adopt the indicator fractionation technique to demonstrate the variation in blood flow between different regions and structure of the brain in cats (Landau, Freygang, Roland, Sokoloff and Kety, 1955). This technique is not applicable clinically since it involves decapitation of the animal. However, Sapirstein (1962) has attempted to apply the same principle using 42K and 131I antipyrine as indicators and external counter uptake measurements for CBF studies in man, albeit with limited success. More recently, the indicator fractionation technique is becoming increasingly widely employed using labelled albumin macroaggregates and scanning techniques for the delineation of infarcted areas and for the quantitation of intracerebral shunts (Nagai, Jimbo and Sano, 1967); earlier misgivings about the safety of the procedure seem to have been largely dispelled by the work of Kennady, Taplin, Griswold and Yamaguchi (1966). Previous article Next article FiguresReferencesRelatedDetails Volume 42, Issue 500August 1969Pages: 561-640 © The British Institute of Radiology History Published onlineMay 29,2014 Metrics Download PDF

Blood flow in the reproductive organs of the mouse after hypophysectomy, after gonadotrophin treatment, during the oestrous cycle and during early pregnancy.

SUMMARY The indicator fractionation technique was examined and found to be of value in the measurement of organ blood flow in the anaesthetized female mouse with [131I]iodoantipyrine as the indicator substance. Blood flow per unit weight of the brain and ovary was shown to decline rapidly after hypophysectomy. A single injection of pregnant mare serum gonadotrophin (PMS), given 4 days after hypophysectomy, restored the blood flow of these organs to normal levels. Uterine blood flow was unaffected by hypophysectomy, and was significantly increased by PMS injection. Significant changes in brain, ovarian and uterine blood flow were observed during the oestrous cycle, early pregnancy and in mice induced to ovulate by injections of gonadotrophin. There was a tendency for brain and ovarian blood flow to decline before ovulation. By contrast, significant transient increases in blood flow to the brain and ovary were observed on day 3 of pregnancy. It is thought that these changes are related to the mechanisms which initiate implantation. Uterine blood flow was lowest in mated and unmated mice on the day of oestrus and rose to peak levels 2 days later. In pregnancy, however, peak uterine blood flow was recorded between days 3 and 4 and was higher than at any stage in the oestrous cycle. Although it tended to fall after day 3, uterine blood flow in pregnancy did not decline again to low levels as it did in the oestrous cycle. The possible physiological significance of the results is discussed, and the limitations to their interpretation are considered.

Cardiovascular changes during lactation in the rat.

SUMMARY The effect of lactation on cardiac output, measured by Fegler's thermodilution technique, and on organ blood flow, measured by Sapirstein's indicator fractionation technique, has been investigated by studying three groups of rats: (1) on day 1 of lactation; (2) on day 12 of lactation, suckling a large litter; (3) on day 12, the young having been removed on day 1. Lactation was accompanied by a significant increase in the weight of the mammary glands, the liver and the small and large intestines and a decrease in the weight of the female reproductive tract and of the skin. Cardiac output in 12-day lactating animals was significantly higher than in non-lactating and in rats on day 1. The proportion of the cardiac output taken by the mammary glands, liver, gastrointestinal tract and their blood flow/g. tissue, increased. Skin blood flow increased, but not that of brain, heart or kidney.

Blood flow to the adrenal cortex and medulla.

The indicator fractionation technique has been applied to the measurement of adrenal cortical and medullary blood flow in the rat. Medullary perfusion per unit of weight is greater than cortical. In stress produced by unilateral carotid artery ligation both cortical and medullary flows increase. The results do not support the hypothesis that stress increases cortical perfusion by medullary arteriolar constriction. (Endocrinology 81: 403,1967)

The Indicator Fractionation Technique for the Study of Regional Blood Flow

The Indicator Fractionation Technique for the Study of Regional Blood Flow

Discussion of “The Indicator Fractionation Technique for the Study of Regional Blood Flow”

Discussion of “The Indicator Fractionation Technique for the Study of Regional Blood Flow”

CHANGES IN BLOOD FLOW AND VASCULAR PERMEABILITY OF THE TESTIS, EPIDIDYMIS AND ACCESSORY REPRODUCTIVE ORGANS OF THE RAT AFTER THE ADMINISTRATION OF CADMIUM CHLORIDE

SUMMARY The effect of s.c. injections of cadmium chloride (3 μmole/100 g. body wt.) on the blood flow and vascular permeability of the testis, epididymis and accessory reproductive organs of rats has been examined. Sapirstein's indicator fractionation technique was used to measure blood flow with [131I]iodoantipyrine and [86Rb]-rubidium chloride. A rubidium-rejecting compartment was found in the testis similar to, but smaller than, that in the brain and pineal body. Testicular blood flow started to decrease within 3 hr. of giving cadmium (Cd) and by 12 hr. was only 2–9 % of the control values; it then started to recover but after 14 days it was still only 31 % of the control values. Apart from a small reduction of blood flow to the first part of the head of the epididymis 6 hr. after Cd administration, blood flow was not strikingly reduced in any part of the epididymis by Cd treatment. However, blood flow to all parts of the epididymis had increased markedly when examined 7 days after giving Cd; this was most evident in the first part of the head of the epididymis. Blood flow through the accessory reproductive organs was reduced within 6 hr. of Cd injection. Blood flow in the seminal vesicles returned to normal between 1 and 14 days after treatment but blood flow in the prostate gland did not recover. The movement of albumin from intravascular to extravascular compartments was used as an index of vascular permeability. This index increased in the testis in the period 1–6 hr. after Cd administration and the change occasionally occurred before blood flow decreased. A similar increase was seen in the first part of the head of the epididymis 3–6 hr. after Cd, but no change was seen in the rest of the epididymis. The evidence suggests that Cd acts by damaging the endothelium of the capillaries in the testis leading to prolonged stoppage of blood flow which would lead to hypoxia in the spermiogenic epithelium.