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PubMed1976

Branchial sodium exchange in seawater-adapted Tilapia mossambica: effects of prolactin and hypophysectomy.

The effects of exogenous prolactin and hypophysectomy were tested on Na exchange across the gills of Tilapia mossambica adapted to sea-water. Exogenous prolactin produced a 75% decrease of both total Na influx and Na efflux. Total Na influx was measured simultaneously with the drinking rate. Water ingestion stopped almost completely in prolactin-treated fish. Thus branchial net excretion flux of Na was reduced 75% by prolactin. Hypophysectomy produced a 50% inhibition of Na efflux across the gill.

Adaptation, Physiological↗
PubMed1976

Effects of adrenalectomy and hypophysectomy on water and electrolyte metabolism in male and female rats with inherited hypothalamic diabetes insipidus (Brattleboro strain).

Observations on water and electrolyte metabolism after hypophysectomy or adrenalectomy, in male and female rats with hereditary hypothalamic diabetes insipidus (Brattleboro strain) are confirmed and extended. The diabetic (homozygous, DI) state relative to the non-diabetic (heterozygous, non-DI) state was characterized by (1) water intake of 55-120% body weight; (2) copious urine hypo-osmotic to plasma; (3) greater excretory rates of total solute, Na, Ca and Mg; (4) similar plasma composition except that in male DI rats, K concentration was less, and in female DI rats osmolarity was higher; (5) glomerular filtration rates (GFR) were similar with close correlations between: food and water intakes, water intake and output, urinary Na and K, Na and Cl, K and Cl, and Ca and Mg; (6) both female DI and non-DI rats had lower urinary Na:K ratios and lower plasma Na concentrations than males; (7) female DI rats excreted relatively larger amounts of K and Cl, and had higher plasma Ca concentrations than other groups. Hypophysectomized DI rats had decreased water intake and urine output, decreased solute excretion, decreased loss of osmotically free water, lower excretory rates of Na, K and Cl, and increased urinary osmolarity and K concentrations. Hypophysectomized non-DI rats had increased urinary excretory rates, decreased solute excretion (by 60-70%), decreased osmotically free water absorption, decreased urinary osmolarity, Na and K concentrations, and increased excretory rates of Ca and Mg. Hypophysectomized DI and non-DI rats had increased plasma osmolarity and Na concentration. Plasma renin activities (PRA) were higher in DI than in non-DI rats with female values lower than those of males; values for both sexes of DI and non-DI rats were reduced after hypophysectomy. Adrenalectomized DI rats had about a 50% reduction in water intake, urine output and free water clearance, increased urinary concentration of electrolytes and total solute by day 4 after operation; their Na balance (dietary:urine) did not change significantly in contrast to adrenalectomized non-DI rats in which a greater percentage of dietary Na appeared in the urine. GFR was similarly reduced in adrenalectomized DI and non-DI rats. Plasma osmolarity increased in adrenalectomized male DI, decreased in female DI and non-DI, and did not change in male non-DI rats. Plasma K concentrations increased after adrenalectomy in all groups, only non-DI rats had a significantly decreased plasma Na concentration. There was no sex difference in pituitary oxytocic activity but it was consistently reduced in DI rats; there was little change after adrenalectomy in male DI and non-DI rats; but there was an increase in DI and non-DI females. Pituitaries of DI rats had no measurable ADH activity (except the inherent activity of oxytocin). Pituitary ADH values for male and female non-DI rats were similar and were unaffected by adrenalectomy.

Adrenal Glands↗
PubMed1978

Blood-testis barrier: evidence for intact inter-Sertoli cell junctions after hypophysectomy in the adult rat.

To study the hormonal dependence of the blood-testis barrier, adult rats were hypophysectomized and the ultrastructural integrity of the inter-Sertoli cell junctional complex was examined at various times with a lanthanum tracer technique. It was found that the structural integrity of the inter-Sertoli cell junctions and their capacity to exclude lanthanum from the adluminal compartment were preserved up to 35 days after hypophysectomy. Furthermore, transport of newly formed spermatocytes through the inter-Sertoli cell junctions still occurred 20 days after hypophysectomy. It is therefore concluded that the function of the inter-Sertoli cell junctional complex is not directly dependent on gonadotrophic or androgenic hormones, but is regulated by other mechanisms.

Animals↗
PubMed1981

In-vitro metabolism of 4-androstene-3,17-dione by hepatic microsomes from the rainbow trout (Salmo gairdnerii): effects of hypophysectomy and oestradiol-17 beta.

The metabolism of 4-androstene-3,17-dione by liver microsomes from juvenile rainbow trout, Salmo gairdnerii, was studied in vitro. Hypophysectomy of the fish significantly increased mean hepatic 17-hydroxysteroid oxidoreductase activity when compared with that from sham-operated fish but none of the other enzyme activities investigated were affected. Administration of oestradiol-17 beta resulted in a significant decrease in mean hepatic 6 beta-hydroxylase activity and total cytochrome P-450 content but had no effect on the 16-hydroxylase or on the reductive metabolism of androstenedione. The effect of oestradiol-17 beta on hepatic 6 beta-hydroxylase activity was as pronounced after hypophysectomy as after sham-operation indicating that these effects of oestradiol-17 beta are mainly direct and independent of the pituitary gland. The results indicate that hypophysial hormone(s) as well as oestradiol-17 betal play a role in the regulation of hepatic steroid metabolism in trout.

17-Hydroxysteroid Dehydrogenases↗
PubMed1982

Effects of oestradiol-17 beta and hypophysectomy on hepatic mixed function oxidases in rainbow trout.

The effects of oestradiol-17 beta and/or hypophysectomy on the metabolism of benzo (a) pyrene (BP), paranitroanisole (PNA), ethylmorphine (EM) and 7-ethoxycoumarin by liver microsomes from juvenile rainbow trout, Salmo gairdnerii, were studied. Administration of oestradiol-17 beta caused significant decrease in the liver microsomal metabolism of BP, PNA and EM while hypophysectomy had no effect. The suppressive effect of oestradiol-17 beta on the mixed function oxidases was as pronounced in hypophysectomized as in sham-operated fish, indicating that this effect of oestradiol-17 beta is mainly direct and independent of the pituitary gland. Administration of oestradiol-17 beta caused a significant increase in the apparent Km values of the PNA-O-demethylase whereas no alteration was seen in the apparent Vmax values of the enzyme. The results indicate that oestradiol-17 beta may play a role in the regulation of hepatic mixed function oxidases in rainbow trout.

Animals↗
PubMed1992

Hypophysectomy prevents the castration-induced increase in porphyrin concentrations in the harderian glands of the male golden hamster: a possible role for prolactin.

The Harderian glands of golden hamsters contain high concentrations of porphyrin pigments, with female hamsters having considerably higher porphyrin concentrations than males. Castration of male hamsters leads to a rapid increase in porphyrin concentrations; testosterone treatment of females has the opposite effect, suggesting a central role for androgens in inhibiting the realization of high porphyrin concentrations by this organ. Previous studies in our laboratories have shown, however, that administration of a dopamine agonist to castrated hamsters prevents the normal increase in Harderian porphyrins from occurring. This suggests that prolactin is necessary for low androgen levels to lead to maximal increases in Harderian porphyrin concentrations. The present study tested the hypothesis that prolactin is involved in the control of Harderian porphyrin levels in the golden hamster. Although hypophysectomy of male hamsters reduced serum testosterone to levels in castrated hamsters, the resultant increase in Harderian porphyrin concentrations was much less than that seen after a similar period of castration. Furthermore, combining the two procedures (castration and hypophysectomy) also led to a blunted increase in Harderian porphyrin, suggesting that a pituitary hormone is necessary for low testosterone levels to lead to increased porphyrins. Evidence that this pituitary hormone is prolactin comes from the observations that eliminating all pituitary hormones except prolactin, by severing the connection of the pituitary with the hypothalamus or transplanting the pituitary to a distant site (beneath the kidney capsule) led to greatly augmented Harderian porphyrin levels, in intact or castrated male hamsters.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Inhibitors of collagen synthesis and hypophysectomy: effects on androgen induced growth of ventral prostate in rats.

To elucidate the effect of decreased amounts of collagen on prostatic growth, beta-aminopropionitrile, one of the agents that selectively inhibit collagen formation, was administered, with or without exogenous androgen and/or hypophysectomy, to rats of varying ages. The weight of the ventral prostate and the collagen content and the ratio of type III to type I collagen in the ventral prostate were examined. Administration of beta-aminopropionitrile, with or without exogenous androgen, reduced the collagen content in the ventral prostate in any age groups, but increased the weight of the ventral prostate only in young rats. Administration of beta-aminopropionitrile to hypophysectomized rats did not change the weight and collagen content. Administration of beta-aminopropionitrile prevented androgen-induced growth of prostatic collagen, resulting in increased prostatic weight in young rat. The ratio of type III to type I collagen in the rat ventral prostate remained unchanged by administration of beta-aminopropionitrile, exogenous androgen, hypophysectomy, or advancing age. It would appear that in young rats prostatic collagen plays an important role in suppressing prostatic growth. The ratio of type III to type I collagen is stable under various experimental conditions in the ventral prostate.

Aminopropionitrile↗
PubMed1977

Pain relief in metastatic cancer other than breast and prostate gland following transsphenoidal hypophysectomy. A preliminary report.

Hypophysectomy was performed in six patients with advanced carcinoma other than from breast and prostate gland to alleviate pain. Two patients received significant and lasting relief of pain; one achieved relief but died from progression of disease 5 weeks after surgery; one patient, initially relieved, had recurrence of pain 3 months later; one had about 50% relief; and one received no benefit. Possible mechanisms for pain relief include changes in pituitary hormones, prostaglandins, and the newly isolated brain peptides, alpha and beta endorphin. These preliminary observations will require further critical evaluation in a larger series to determine the effectiveness of hypophysectomy in relieving pain in cancer other than from the breast and prostate. The results, nevertheless, do imply that a different approach to pain, namely endocrine manipulation, may be beneficial in certain cancer patients.

Adult↗
PubMed1979

An improved transbuccal approach for hypophysectomy in the domestic fowl.

The present paper describes an improved transbuccal approach for hypophysectomy in the domestic fowl. With this technique, the operative procedures are the same as in the transbuccal approach of Hill and Parkes (1934), except that the drilling angle is the same as in the oral approach of Rothchild (1948a,b), since the present anatomical investigation indicates that the hypophysis lies at an angle of 45 degrees to the surface of the palate. An apparatus that was made to restrain the fowl head facilitates the operative procedure; even a novice can perform fowl hypophysectomy in more than 70% of the cases.

Animals↗
PubMed1988

Effect of hypophysectomy on 17 alpha-hydroxylase activity in theca cells of the ovarian follicle in the Japanese quail.

The activity of 17 alpha-hydroxylase, a key enzyme for progesterone metabolism in avian follicles, was measured in cell-free homogenates of isolated theca cells of Japanese quail. Kinetic studies revealed that differences in enzyme activity in the largest and the second largest follicles were mainly due to differences in Vmax values. In order to investigate the mechanism of regulation of 17 alpha-hydroxylase activity, quail were hypophysectomized at various time periods during the ovulatory cycle, and 17 alpha-hydroxylase activity in theca homogenates was measured 4 h after surgery. Hypophysectomy at 8 h before the predicted time of ovulation, which is the time when the preovulatory luteinizing hormone (LH) surge is initiated, resulted in a significant decrease in enzyme activity. In contrast, activity was increased when the pituitary was removed 20 h before ovulation. Hypophysectomy 24 h before ovulation had no effect on enzyme activity.

Animals↗
PubMed1975

Effect of hypophysectomy on the volume and ultrastructure of zona glomerulosa in rat adrenal.

The zona glomerulosa of the rat has been examined at various times after hypophysectomy. There is no detectable change in the zona glomerulosa at 2 days after hypophysectomy. However by 7 days, the width of the glomerulosa became significantly larger in spite of an absolute decrease in the volume of the zone. No alternations in ultrastructure were discernible at this time in the glomerulosa, although giant mitochondria were seen in adjacent zona fasciculata cells. By 30 days there was a much wider zona glomerulosa and a restoration of the volume of the zone to that found in controls. Many zona glomerulosa cells were hypertrophic. The Golgi apparatus was enlarged and many vesicles were associated with peripheral cisternae. A few intramitochondrial tubules were observed in some mitochondria of the zona glomerulosa at 30 days.

Adrenal Cortex↗
PubMed1975

[Swelling of neurosecretory fibers (Herring bodies) in the reorganized hypophyseal stalk following hypophysectomy].

Herring bodies were revealed in the reorganized hypophyseal stalk of rats two months after hypophysectomy both in normal laboratory condition and under salt load. We observed Herring bodies with a storage of neurosecretory granules and neurohormones, as well as with massive destruction and disappearance of neurosecretory granules due to release of hormones in neuroplasm. Many Herring bodies were characterized by degenerative changes probably associated with aging of neurosecretory cells or their lesion due to the operation. Occasionally we revealed Herring bodies which contained a network of dilated neurotubules, that probably reflected either the reparative phase of secretory cycle of corresponding neurosecretory cells or restoration of their functions after hypophysectomy. Herring bodies were often situated around capillaries, but they were separated from perivascular space with narrow sprouts of pituicytes.

Animals↗
PubMed1975

The treatment of acromegaly with special reference to trans-sphenoidal hypophysectomy.

Experience in the management of 100 cases of acromegaly is described. Three quarters of these had been referred directly to the endocrine clinic at the Middlesex Hospital. The remainder were referred from the Royal Post-graduate Hospital because they were thought unsuitable for yttrium implantation. The patients were studied by clinical assessment of severity, by measurement of basal growth hormone levels on three separate mornings, and by a review of possible complications. Particular attention was paid to diabetes, hypertension, cardiomegaly, respiratory, vascular and skeletal changes as well as visual field defect. Aggressive treatment was recommended in 77 patients. It was not recommended in the remainder on account of age, intercurrent illness or the apparent mildness of the condition. Fifty-nine patients were treated by trans-sphenoidal hypophysectomy. In 46 of the 59 patients the mean basal growth hormone level has been reduced to 5 ng/ml or less. In 39 this followed operation, in five operation and subsequent X-ray therapy and in two operation and the continuing effect of previously implanted yttrium. Of these 46 patients in whom the growth hormone level has been reduced to normal, 26 do not show any deficiency of anterior pituitary trophic hormones, 13 have gonadotrophin defect (in eight of these it was present before the operation) and seven require full replacement therapy. One patient died at home six weeks after the operation from a pulmonary embolus. There was one case of CSF rhinorrhoea which stopped spontaneously and three of acute frontal sinusitis. Trans-sphenoidal hypophysectomy is shown to be an effective means of treating acromegaly. If the basal level of growth hormone is not reduced to normal by six weeks after operation, it is recommended that a course of X-ray therapy should be given. This does not apply if irradiation has been used before operation.

Acromegaly↗
PubMed1956

A technique for hypophysectomy.

The procedure of hypophysectomy may offer some hope in metastatic carcinoma of the breast. Certainly further clinical trial is indicated. The anterior intracranial approach through the sphenoid sinus was used in eight cases. It offers a technically easier route by which to perform hypophysectomy. The immediate risk of operation does not appear to be too great. Caution must be urged against delaying this procedure until the patient is in a terminal condition.

Carcinoma↗
PubMed1977

Estimation of pregnenolone synthesis in rat adrenal homogenates: some cofactor requirements: effects of stress, hypophysectomy, cortisone and ACTH.

Pregnenolone synthesis was estimated in whole adrenal homogenates incubated in the presence of cyanoketone (2alpha-cyano-4,4,17alpha-trimethyl-androst-5-en-17beta-ol-3-one). The yield of pregnenolone depended on the type of incubation medium employed. Both Ca++ and bovine serum albumin (BSA) markedly stimulated the rate of pregnenolone synthesis as did NADPH or NADPH generating system. Aminoglutethimide added in vitro inhibited cholesterol sidechain cleavage activity. Ether stress in vivo stimulated pregnenolone synthesis in vitro, and hypophysectomy of 24 hours duration resulted in a decrease. Cortisone administration for 8 days reduced the formation of pregnenolone by rat adrenal homogenates, an effect prevented by concomitant treatment with ACTH. Similarly, hypophysectomy of 8 days duration resulted in a marked diminution of pregnenolone synthesis and ACTH replacement reversed this effect. Changes in pregnenolone synthesis were paralleled by changes in corticosterone and total steroid production.

Adrenal Glands↗
PubMedDate not supplied

Isolated sphenoid sinusitis after transsphenoidal hypophysectomy.

BACKGROUND: Literature addressing the incidence and management of sinusitis after transsphenoidal hypophysectomy is sparse. METHODS: Retrospective chart analysis was conducted on 200 consecutive patients who had undergone transsphenoidal procedures between January 1998 and December 2001. The postoperative incidence of sinusitis was determined. Clinical characteristics, management strategy, and outcome were reviewed. RESULTS: Fifteen of the 200 patients (7.5%) developed rhinosinusitis after transsphenoidal surgery. Seven of the patients were referred to otorhinolaryngology for further management. Three additional patients, who had undergone transsphenoidal hypophysectomy at outside institutions, also were evaluated during this time. Nine of 10 patients (90%) had isolated sphenoid sinusitis by computed tomography and/or endoscopic criteria. The most common symptoms included headaches and nasal discharge present for an average of 2.9 years. Medical management resulted in resolution of symptoms in 5 of 10 cases (50%). The remaining five patients required endoscopic sphenoidotomy for recalcitrant disease. Intraoperatively, fungal balls were identified in three cases. Mucocele formation was encountered in one case, and an infected fat graft was evident in one case. Sphenoid sinusitis was resolved successfully in all 10 cases. CONCLUSION: A high index of suspicion must be maintained to avoid an inordinate delay in diagnosis of isolated sphenoid sinusitis in this setting, in light of the nonspecific presentation of this clinical entity. Aggressive medical and/or surgical treatment is required for resolution of refractory symptoms in this patient population.

Female↗
PubMed2006

Technique for performance and evaluation of parapharyngeal hypophysectomy in mice.

Mice at our institution were hypophysectomized to evaluate the effects of growth hormone on the expression of a transfected human factor IX gene. The hypophysectomy was performed in-house by using a parapharyngeal approach modified from previously published surgical techniques. Modifications included: 1) choice of ketamine-xylazine and isoflurane for anesthesia, with butorphanol for postoperative analgesia; 2) use of a V-trough for positioning mice correctly and consistently; 3) selection of increasing sizes of dental burrs to create a foramen in the cranial base through which the pituitary gland was removed; and 4) disuse of a tracheotomy for airway patency. In addition, verification of successful gland removal was assessed by measuring major urinary protein (MUP) in the urine; presence of MUP indicated incomplete hypophysectomy. This assessment enabled antemortem determination of surgical success by using a single urine collection. Each of these modifications contributed to the success of the surgical procedure. We had a safe and reliable anesthetic regimen, consistent positioning of the surgical patient, and smooth and rapid penetration of the cranium. In our experience, the tracheotomy described in previous techniques was unnecessary, as the mice tolerated brief periods of apnea (approximately 5 sec maximum) while the trachea was retracted. Here we seek to provide details that will assist those interested in learning this technique and that will reduce the number of mice needed for practice. Other applications include a method of evaluating the production of growth hormone without euthanizing the animal.

Anesthesia↗
PubMed1991

[Hypophysectomy as a possible therapy in prostatic carcinoma].

Hypophysectomy had been introduced in the therapy of advanced stages of prostatic carcinoma at the Clinic of Urology, University Hospital in Olomouc, in collaboration with the Research Institute of Higher Nervous Activity, 10 years ago. The tissue of the hypophysis is disintegrated thermodynamically which was performed in 19 patients. At the time of indication for this intervention, three patients had tumor in the stage T3, others in the stage T4. Metastatic spread to regional lymph nodes and skeleton was encountered in all cases. In 2 patients the grade of tumor activity was G2, in others G3. The intervention was indicated due to patient's permanent pains resistant to pharmacological alleviation. The life-span after intervention was 1 month up to 4 years. Remission was recorded in 70% of patients. Changes in serum levels of some hormones after various types of hormone therapy and hypophysectomy are compared.

Aged↗