Effluent Blood Research Articles

The glycogenolytic response to stimulation of the splanchnic nerves in adrenalectomized calves.

1. The effects of stimulation of the peripheral ends of one or both splanchnic nerves have been investigated in adrenalectomized calves at different ages.2. During the first 24 hr after birth unilateral splanchnic nerve stimulation led to a prompt rise in the plasma glucose concentration and this response was more than doubled when both nerves were stimulated simultaneously. Under these latter conditions hyperglycaemia was found to be associated with a measurable loss of glycogen from the liver.3. Both the glycogenolytic and hyperglycaemic effects of splanchnic stimulation became more pronounced with age; at 5 weeks of age liver glycogen was depleted by approximately 2/3 and plasma glucose raised by about 200 mg/100 ml. after stimulation of the right splanchnic nerve for 9 min.4. Splanchnic stimulation also caused a rise in mean arterial blood pressure and haematocrit during the period of stimulation at all ages studied; the rise in haematocrit was greatest in the oldest animals.5. The hyperglycaemic response to splanchnic stimulation persisted after pancreatectomy and was also demonstrated in calves in which the whole of the portal effluent blood flow was collected during splanchnic stimulation. The plasma from blood collected in this way had no apparent hyperglycaemic effect when infused into a branch of the mesenteric vein in recipient calves.6. In adrenalectomized calves in which the liver had been partially denervated before stimulation both the hyperglycaemic and the glycogenolytic responses were substantially reduced, although the rise in haematocrit was unaffected, during stimulation of both splanchnic nerves.7. It is concluded that glycogenolysis occurs in the liver as a result of stimulation via the hepatic innervation in the new-born calf and that this response increases with age during the first few weeks after birth.

Lactic acid formation in gastrocnemius muscle of the dog and its relation to O 2 debt contraction

The O 2 debt determined as the O 2 uptake deficit at the beginning of exercise may be entirely attributed to the depletion of O 2 stores and to the hydrolysis of high energy phosphates as the lactic acid formation in the isolated dog gastrocnemius preparation is very small and taking place at a constant rate from the beginning of stimulation. The lactic acid concentration in the muscle is roughly equal to that in effluent blood both at rest and during exercise.

Hormone Secretion by the Human Ovaries

The secretory function of both human ovaries was studied simultaneously by comparing the concentrations of several steroids in the effluent blood from the two ovaries with their concentrations in the peripheral blood. As expected, progesterone and estradiol emerged as important secretory products. In both the preovulatory and postovulatory phases of the menstrual cycle, significant amounts of 17Α-hydroxyprogesterone and androstenedione were found. In two cases dehydroepiandrosterone was present in high concentration in ovarian vein blood. 20Α-hydroxy-4-pregnene-3-one, but not 20Β-hydroxy-4-pregnene-3-one, was consistently secreted by the corpus luteum. Small amounts of estrone and testosterone may be secreted by the ovary. In two ases with bilateral ovulation, there was a similarity between the steroid output of the two corpora lutea. In one subject studied following clomiphene treatment, anatomical as well as biochemical vidence of a hyperstimulated state was demonstrated. None of the steroids studied were secreted by the ovaries of a postmenopausal woman with the possible exception of androstenedione. While the bulk of the hormones was secreted by the ovary bearing the ripe follicle or the corpus luteum, the data indicate that the contralateral ovary actively secretes androgenic steroid hormones, especially androstenedione.

Mechanisms of intra-arterial Kplus-induced cardiovascular and respiratory responses.

ARTICLESMechanisms of intra-arterial Kplus-induced cardiovascular and respiratory responsesCT Liu, RA Huggins, and HE HoffCT Liu, RA Huggins, and HE HoffPublished Online:01 Oct 1969https://doi.org/10.1152/ajplegacy.1969.217.4.969MoreSectionsPDF (1 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByReflexes Controlling Circulatory, Ventilatory and Airway Responses to Exercise1 January 2011Divergence of ventilatory responses to isometric contraction in anesthetized catsRespiration Physiology, Vol. 104, No. 2-3Comparison of blood pressure and heart rate responses to isometric exercise and passive muscle stretch in humans1 March 1995 | European Journal of Applied Physiology and Occupational Physiology, Vol. 70, No. 3Blood pressure and heart rate during rest-exercise and exercise-rest transitionsEuropean Journal of Applied Physiology and Occupational Physiology, Vol. 64, No. 2Cardiovascular reflexes during sustained handgrip exercise: role of muscle fibre composition, potassium and lactateEuropean Journal of Applied Physiology and Occupational Physiology, Vol. 65, No. 4Reduction in extracellular muscle volume increases heart rate and blood pressure response to isometric exerciseEuropean Journal of Applied Physiology and Occupational Physiology, Vol. 60, No. 3The influence of muscle interstitial volume on K+-induced heart rate drive in ratsEuropean Journal of Applied Physiology and Occupational Physiology, Vol. 57, No. 1Response of chemosensitive nerve fibers of group III and IV to metabolic changes in rat musclesPfl�gers Archiv European Journal of Physiology, Vol. 410, No. 1-2Congestive cardiac failure: central role of the arterial blood pressure.Heart, Vol. 58, No. 3LiteraturRespiratory Control During Exercise1 January 2011Slowly Conducting Afferent Fibers from Deep Tissues: Neurobiological Properties and Central Nervous ActionsCirculation to Skeletal Muscle1 January 2011Cardiovascular Reflex Control by Afferent Fibers from Skeletal Muscle Receptors1 January 2011Cardiovascular Adjustments to Isometric Contractions: Static Effort1 January 2011Changes in heart rate and blood pressure upon injection of algesic agents into skeletal musclePfl�gers Archiv European Journal of Physiology, Vol. 393, No. 1ON REFLEX CONTROL OF EXERCISE HYPERPNEA FROM MUSCULAR RECEPTORSPERIPHERAL NEURAL CONTROL OF CARDIOVASCULAR AND RESPIRATORY RESPONSES TO ISOMETRIC EXERCISEReflex inputs to the cardiovascular and respiratory centers from dynamically working canine muscles. Some evidence for involvement of group III or IV nerve fibers.Circulation Research, Vol. 41, No. 3Effect of contraction on lymphatic, venous, and tissue electrolytes and metabolites in rabbit skeletal musclePfl�gers Archiv European Journal of Physiology, Vol. 368, No. 3Work-induced potassium changes in skeletal muscle and effluent venous blood assessed by liquid ion-exchanger microelectrodesPflügers Archiv European Journal of Physiology, Vol. 362, No. 1Work-Induced potassium changes in muscle venous effluent blood measured by ion-specific electrodesPflügers Archiv European Journal of Physiology, Vol. 338, No. 2Work-induced increase of extracellular potassium concentration in muscle measured by ion-specific electrodesBrain Research, Vol. 40, No. 2 More from this issue > Volume 217Issue 4October 1969Pages 969-973 Copyright & PermissionsCopyright © 1969 by American Physiological Societyhttps://doi.org/10.1152/ajplegacy.1969.217.4.969PubMed5824336History Published online 1 October 1969 Published in print 1 October 1969 Metrics

THE FATE OF FREE AND CONJUGATED OESTROGENS INJECTED INTO THE GRAAFIAN FOLLICLE OF EQUINES

SUMMARY [4-14C]Oestradiol-17β, [4-14C]oestrone, Na[6,7-3H]oestradiol-17β-glucuronide and Na[6,7-3H]oestrone sulphate were injected into a Graafian follicle of two mares and a donkey after cannulation of the ovarian vein. Radioactivity was measured in follicular fluid and ovarian venous blood at different intervals after injection and in tissue and interstitial fluid at the end of the operation. Both free and conjugated oestrogens were retained to a great extent in the follicle, in the presence of constant production of endogenous oestrogens. Only a small portion of the oestrogen released from the follicle passed directly into the ovarian venous blood; a larger portion entered the effluent blood indirectly, through interstitial fluid and tissue. The conjugates, particularly the glucuronide, seemed to be excluded from the cells and accumulated in the interstitial fluid. The role of binding of oestrogens to fluid proteins in the retention of oestrogen in follicular fluid is discussed.

Adrenal response to hypophysectomy in the newborn dog.

SummaryHypophysectomy in the newborn dog results in a prompt fall in the secretory rate of cortisol during collection of adrenal effluent blood. Due to the rapid rate of clearance of ACTH, lowest secretory rates were expected at 2–5 hr after hypophysectomy but, at 16–20 hr, an even lower rate was found. This unexplained observation was significant. The procedure of hypophysectomy recommends itself as a valuable means of exploring the endocrinologic status of the newborn.

Absorption of acetate-1-C14 from the reticulo-rumen of Calves 3 to 4 days old

Abstract The ability of calves to absorb and metabolise steam volatile fatty acids (VFA) was investigated by the introduction of acetate–l–C14 into the rumen of three anaesthetised animals 3 to 4 days old. Acetate–l–C14 appearance in rumen effluent blood and clearance from peripheral blood were considered sufficient evidence of assimilation and utilisation respectively. All the calves absorbed and rapidly metabolised the isotope.

Correlation of the secretion of ovarian steroids with function of a single generation of corpora lutea in the immature rat.

Ovulation and luteinization have been artificially induced in prepuberal rats by the administration of 4 IU PMS. Evidence for luteal function was provided by the establishment of pseudopregnancy and the induction of deciduomata. The animal preparation has been successfully used to determine the secretory pattern of ovarian steroids during the first ovulation cycle and pseudopregnancy, to obtain quantitative data on the “functional” capacity of the first generation corpora lutea, and to relate ovarian 20α-OH-steroid dehydrogenase activityactivity to luteal function. Preovulatory secretion of progesterone has been related to the discharge of the ovulating hormone. Post-ovulatory secretion of progesterone has been correlated with luteal function. Ovarian 20α-OH-steroid dehydrogenase activity, localized biochemically in the corpora lutea, provided an index of luteolysis. Increasing enzyme activity resulted in increased 20α-OH-pregn-4-en-3-one and reduced progesterone concentrations in ovarian effluent blood a...

Patterns of steroidogenesis in the vertebrate gonads

Over the past ten years data have been published on the biosynthesis of androgens and estrogens from Δ 5-pregnenolone in vertebrate gonads via two metabolic pathways—one pathway (A) using progesterone and 17α-hydroxyprogesterone as intermediates and another pathway (B) biotransforming Δ 5-pregnenolone to androgens and estrogens via 17α-hydroxypregnenolone, dehydroepiandrosterone, and Δ 5-androstenediol. We have investigated these problems in the canine testis and in the canine ovary in experiments in vivo. Since 17α-hydroxypregnenolone can be metabolized to 17α-hydroxyprogesterone in the gonads from both sexes, metabolic pathway B and metabolic pathway A may overlap. Thus, testosterone can be produced in the canine testis bypassing the formation of the steroid hormone progesterone. In the canine ovary androgens and estrogens can indeed be formed from Δ 5-pregnenolone via pathway B, but since progesterone is an important secretory product of the ovary, the preferred route for Δ 5-pregnenolone biotransformation in this tissue is pathway A. In the canine testis, the level of secretion of dehydroepiandrosterone and 17α-hydroxyprogesterone is much higher than that of either Δ 5-pregnenolone or progesterone. The metabolic pool of 17α-hydroxyprogesterone in the canine testis is larger than its pool of progesterone. Moreover, there may be one storage pool and one secretory pool for steroids and steroid hormones in the gonad of the male dog. These pools are not of the same size. Progesterone is rapidly converted to either 17α-hydroxyprogesterone or to Δ 5-pregnenolone by the dog testis, and the direct conversion of progesterone to testosterone (acetate) in this tissue is so small that it cannot be measured by currently available techniques. The rate of secretion of estrone and estradiol by the canine testis is minute. Since both the canine adrenal gland and the canine testis secrete the intermediates of pathway A and of pathway B into venous, effluent blood, the importance of this secretion for the allover hormonal household of the male dog will be discussed. This aspect of steroid metabolism appears to be important. It has recently been observed that when adrenal venous blood is infused via the spermatic artery of the dog, the secretion of testosterone by the infused testis is significantly increased. Thus, reutilization of steroid intermediates, secreted by the adrenal gland, can take place in vivo. Data will finally be presented on the effects of human chorionic gonadotropin (HCG), adenosine 3′,5′-monophosphate (3′,5′-AMP) and prostaglandin (PG) on testicular metabolism of Δ 5-pregnenolone to androgens. In these experiments special emphasis is placed on how HCG, 3′,5′-AMP. or PG can change testicular storage and testicular secretion of the intermediates from pathway A and from pathway B.

Thyrocalcitonin. Its role in calcium homeostasis.

The discovery of a new hormone is indeed a rare and exciting occurrence. Most of the recent advances in the field of endocrinology have emanated from the chemical characterization and purification of known hormones. The precise regulation of blood calcium under the principal control of parathyroid hormone acting on bone, intestine, and kidneys has been recognized and elucidated in the past 40 years. In 1961, this classic concept was challenged as a result of the demonstration of a second substance involved in calcium homeostasis. The historical development, present status, and possible clinical implications of this new hypocalcemic principle are the subject of this review. The original evidence for a plasma calcium lowering hormone came from experiments on dogs by Copp and his colleagues. 1-4 The thyroparathyroid apparatus was perfused with high, then low, calcium containing blood and the effluent blood returned to the systemic circulation. Hypercalcemic perfusion was found to

Studies on the relationship of serum and pituitary gonadotrophin levels to ovulation in the ewe.

Observed reductions in the pituitary content of follicle stimulating hormone (fsh) and luteinizing hormone (lh) preceding ovulation in sheep (Santolucito, Clegg & Cole, 1960; Robertson & Hutchinson, 1962; Dierschke & Clegg, 1965; Robertson & Rakha, 1966) clearly imply that both hormones are involved in bringing about this event. These observations regarding pituitary content would seem to provide acceptable criteria for hormone release, but determination of the precise time and interval of gonadotrophin release must be confirmed by quantitative analysis of blood fsh and lh. This communication reports an attempt to accomplish that confirmation utilizing a technique for collecting pituitary effluent blood from the cavernous sinus of sheep (McFarland, Clegg & Ganong, 1960) and the highly sensitive biological assay of Parlow (1961) for lh. Assay of pituitary fsh was done by the method of Steelman

Effect of gonadotrophins on the secretion of progesterone and oestrogens by the sheep ovary perfused in situ.

Summary. The effect of gonadotrophins on the secretion rate of gonadal hormones in sheep was investigated by perfusing the ovary in situ with luteinizing hormone (lh), luteotrophic hormone (lth) and follicle stimulating hormone (fsh). The gonadotrophins were infused through the side branch of the ovarian artery and the effluent blood was collected from the utero-ovarian vein. Perfusion of the ovary on the 8th day of the oestrous cycle with lh or lth resulted in the increase of the secretion rate of progesterone within 20 to 30 min after the beginning of the perfusion; when the perfusion of the ovary was terminated the rate of progesterone secretion reverted to the original level within 20 to 30 min. Unlike lh and lth, fsh infused on the 8th day of the oestrous cycle decreased the output of progesterone. On the 15th day of oestrous cycle progesterone could not be detected in the effluent blood from the ovarian vein. At that time, perfusion of the ovaries with gonadotrophic hormones produced no effect on the secretion rate of progesterone. Substances giving positive reaction with Barton's reagent and showing chromatographic characteristics of oestrone and oestradiol were detected in the ovarian venous blood in few animals only, and in very low concentrations. No relation was observed between the presence of these substances in the ovarian venous blood and either the phase of oestrous cycle or the type of gonadotrophin infused. Furthermore, perfusion of the ovary with fsh or lh resulted in the appearance in the ovarian venous blood of an unknown oestrogen-like substance of higher polarity than that of oestrone but lower than that of oestradiol.

Physiological changes in blood bradykinin levels in man.

SummaryUsing a sensitive method of blood bradykinin estimation, arterial and venous levels were compared in the human forearm. Arterial levels were usually higher, the ratio of arterial to venous levels ranging from 4 to approx. 1.Changes in blood bradykinin in venous blood from the hand were studied during hyperaemic states in the hand produced by warming, cooling and ischaemia. Increas of bradykinin up to 53% in effluent blood from the hand occurred when the hand was warmed to 45°. However, bradykinin levels fell in the dffluent blood in association with reactive hyperaemia and cold vasodilatation.An increase in sympathetic nervous activity caused a fall in arterial bradykinin level of 20% in one case and almost complete disappearance in another Generalised sympathetic blockade with bethanidine brought about a 7·5‐fold increaseThe ability of increased sympathetic nervous activity to lower blood bradykinin level may possibly contribute to the decreased venous bradykinin levels found in cold vasodilatation and reactive hyperaemia where an increase in sympathetic nervous activity occurs a result of the pain and discomfort associated with these procedures.

Collection of hypophysial stalk blood in rats.

A method for collecting all the effluent blood of the hypophysial stalk in rats is described. This blood is believed to be free of contamination with extraneous blood and with cerebrospinal fluid. The average duration of the collection periods in a group of 40 adult male rats was 4.6 hr. The range of the collection periods extended from 2.75 to 6 hr. The use of this method as a preliminary procedure in the determination of secretory rates of the hypothalamic releasing factors is discussed. (Endocrinology 81: 1182, 1967)

Measurement of Renin in Both Renal Veins

THE RECENT development of a simple reliable method for measuring plasma renin activity, together with the availability of a safe procedure for obtaining samples of blood from both renal veins, has prompted us to assess the utility of such measurements in the diagnosis of surgically correctable renovascular hypertension. Previous studies of this type have been reported by McPhaul, 1 Fitz, 2 Kirkendall, 3 and Ueda, 4 and their associates. A series of 22 patients, diagnosed by conventional measures as having renovascular hypertension, were subjected to operative treatment. Proof of the diagnosis was considered to be established if there was unquestionable improvement in blood pressure after corrective surgery. This is a report of the measurements of renin activity in blood plasma specimens obtained from both renal veins preoperatively and, whenever possible, postoperatively. In addition, plasma renin activity in effluent blood from both kidneys was measured in 13 patients with "essential" hypertension, who were not subjected

Maintenance and function of corpora lutea in rabbits depend on estrogen.

Pregnant rabbits with one X-irradiated ovary which contained normal-appearing corpora lutea (CL) and interstitial tissue aborted after removal of the contralateral normal ovary containing all ovarian components. The suspicion that estrogen may be essential for CL maintenance and function was confirmed by the injection of estradiol (2–4 μg/day) into rabbits with only an X-irradiated ovary containing just CL and interstitial tissue. Pregnancy was maintained in these females and both the CL and the ovarian effluent blood contained chemically measurable quantities of progesterone. Withdrawal of estrogen caused cessation of progesterone synthesis and secretion and led to abortion. At doses used, neither purified NIH-LH nor crude anterior pituitary powder could, in the absence of estrogen, maintain either the morphology of corpora lutea, or the synthesis of progesterone, or pregnancy. The conclusion is reached and documented that estrogen may act directly on the CL but whether its action is only luteotrophic, or both luteotrophic and steroidogenic, remains to be determined. (Endocrinology80: 938, 1967)

Progestin Levels in the Ovaries and Ovarian Effluent Blood in Pregnant Rabbits.

54 adult rabbits were assigned to 1 of 3 groups pregnant pseudopregnant or superovulated and employed in determining progestin levels in ovaries and ovarian effluent blood. Progesterone and 20-alpha-hydroxy-pregn-4-ene-3-one (20 alpha-ol) were measured chemically at different stages of pregnancy or pseudopregnancy. During pregnancy the level of progesterone averaged .7 mcg/ml at Day 4 and 1.3 mcg/ml at Day 20 of pregnancy. The level of 20 alpha-ol in the ovarian blood varied from .2-1.5 mcg/ml with only slight correlation to the stage of pregnancy. Progestin levels correlated neither with number of corpora lutea nor to number of viable or degeneration implantations. At 9 days postcoitum the total amount of ovarian progesterone was higher in pregnant than in pseudopregnant does; this was not the case for 20 alpha-ol. The levels and total amount of 20 alpha-ol in the ovaries were 2-5 times those of progesterone. There was a correlation between the concentration of progesterone levels and 20 alpha-ol in the ovaries and that of the blood during pregnancy.

The Secretion of Adrenal Medullary Hormones During Hypoglycemia in Intact, Decerebrate and Spinal Sheep2

AbstractIt is not known from which part of the central nervous system the adrenal medulla is activated in hypoglycemia. The question was investigated in animals with various parts of the central nervous system removed, and the adrenal response was compared with that of intact animals. The amounts of adrenaline and noradrenaline in adrenal effluent blood were determined fluorimetrically. Intact animals showed increased secretion rate of adrenaline and to a lesser degree of noradrenaline in response to hypoglycemia. Decerebrate animals were capable of activating their adrenal medulla during hypoglycemia while spinal animals did not increase the rate of secretion above the resting level. It is, therefore, concluded that sympathetic neurones situated in the brain stem caudal to the hypothalamus are capable of activating the adrenal medulla in hypoglycemia. It proved very difficult to lower the blood glucose concentration in decerebrate animals despite the administration of large doses of insulin. The mechanism behind the insulin resistance of the decerebrate animal is discussed.

Effect of testosterone, progestagens, and metopirone on adrenal activity in cockerels

Adrenal weight was reduced when growing cockerels were treated with Provera or Prodox. Metopirone, Prodox, or testosterone lowered the amount of corticosterone in adrenal effluent blood of stressed chickens, but testosterone was effective only in castrated birds. Corticosterone had a half-life of about one-half hour in capons. Treatment of castrates with testosterone did not alter the clearance of exogenous corticosterone from plasma, but the biosynthesis of corticosterone by adrenal tissue in vitro was inhibited by a testosterone concentration of 3.47 × 10 −4 M

Absence of ACTH-like activity in nocardia asteroides

Seventeen-hydroxycorticosteroid determinations were done on adrenal effluent blood from intact and hypophysectomized dogs before and after injection of ACTH, Nocardia asteroides lysate, and supernatent culture medium. The lysate and culture medium caused an increase in secretion of 17-OHCS in the intact animals but not in the hypophysectomized animals. This indicates that the organism does not form an ACTH-like material previously suggested as an explanation for the simultaneous occurrence of nocardiosis and Cushing's syndrome.