SEARCH · Search PubMed

Results for “ADRENALECTOMY”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 991 records · Page 55Linked to original sources

PubMed1978

Effects of adrenalectomy and constant light on the rat estrous cycle.

Adult female ARS/Sprague-Dawley rats were allowed to acclimatize to a a lighting schedule of 12L:12D (LD) for 5 weeks. At that time, half the animals were adrenalectomized, and all rats remained in LD for an additional 4 to 5 weeks. Subsequently, half of the control and half of the adrenalectomized rats were exposed to constant light (LL) for an additional 8 weeks, at which time all animals were sacificed. Operated rats with regenerated adrenal tissue, determined either by macroscopic examination or serum corticosterone assay (about 50% of the rats), were excluded from all data calculations. Acute disturbances of estrous cycle length were minor. The long-term effects revealed a significant increase in 5-day cycles among the adrenalectomized rats, although the majority of cycles recorded (80%) were still 4 days in length. None of the rats in LD showed spontaneous persistent estrus. Adrenalectomy did not affect the number of ova shed. When placed in LL, the adrenalectomized rats continued to cycle longer than the unoperated controls, but all rats showed persistent estrus (5 or more consecutive days of vaginal cornification) within 7--8 weeks. Adrenalectomized rats had significantly higher body weights than controls. Relative uterine weight was decreased in these animals in both lighting regimens but only reached statistical significance in LD. Ovarian weight, by contrast, was significantly increased among adrenalectomized rats in LD but was identical in both groups in LL. Adrenal weight of intact rats was not altered by LL. Since estrous cycles can continue for at least 6 months in the absence of the adrenal gland, the persistent estrus that occurs in LL is not merely due to the loss of a diurnal rhythm of corticosteroids. Indeed, when adrenalectomized rats are placed in LL, they continue to show estrous cycles longer than do intact rats. Adrenalectomy does appear to increase the length of the cycle in some animals, and the hormonal basis for this warrants further study.

Adrenalectomy↗

PubMed1979

Effects of septal lesions and adrenalectomies on the acquisition and extinction of shuttle avoidance in the rat.

Rats with septal lesions and rats with both septal lesions and adrenalectomies (SEP-ADX) acquired avoidance behaviors faster and extinguished these behaviors slower than rats with adrenalectomies or control lesions. Rats with septal lesions also showed increased intertrial crossings during habituation, acquisition, and extinction while rats in group SEP-ADX only had increased intertrial crossings during acquisition. These findings are consistent with the hypothesis that the avoidance performance of rats with septal lesions is a result of neural rather than hormonal factors.

Adrenalectomy↗

PubMed1989

Effects of unilateral adrenalectomy on the remaining adrenal cortex of adrenocorticotropic hormone-treated male and female hamsters.

Sham-operated and unilaterally adrenalectomized male and female hamsters were administered 25 micrograms adrenocorticotropic hormone (ACTH) for 5 days after the operation in order to examine the effects of ACTH on compensatory adrenal growth. In ACTH-treated male and female hamsters, unilateral adrenalectomy did not change the relative weight of the remaining adrenal. There were no significant differences in the volumes of the adrenocortical zones and their parenchymal cells, as well as in the number of adrenocortical cells per gland if compared with unilaterally adrenalectomized and sham-operated ACTH-treated male hamsters, while 3H-thymidine incorporation per gland was lower in monoadrenalectomized animals. On the contrary, in ACTH-treated females, unilateral adrenalectomy resulted in a significant hypertrophy of zona fasciculata cells and in an enhanced 3H-thymidine uptake by the remaining gland. These findings stress the existence of notable sex-related differences in the compensatory adrenal growth in hamsters.

Adrenal Cortex↗

PubMed1990

Immunoelectron-microscopic and morphometric study of the rat corticotrophs after adrenalectomy.

The ultrastructural changes of rat corticotrophs were studied with the protein-A-gold immunocytochemistry. The number of secretory granules per square micrometer of cytoplasm decreased after adrenalectomy and remained low. This change was mainly due to the decrease in the mature granules. The number of gold particles on the secretory granule was increased 3 or 7 days after adrenalectomy, reflecting the high immunoreactive adrenocorticotropin content in these states as has been already reported. The number of coated pits or coated vesicles beneath the plasma membrane was not increased significantly, and exocytosis was only infrequently observed. Ultrastructural changes which suggest a secretion pathway other than the secretory granules were not observed.

Adrenalectomy↗

PubMed1988

Reduction of urea generation and muscle protein degradation by adrenalectomy in acutely uremic rats.

The effect of adrenalectomy on the enhanced protein degradation in acute uremia was investigated. Therefore, serum urea nitrogen, urea N appearance and Nt-methylhistidine were followed in bilaterally nephrectomized rats. At 48 h after induction of uremia the animals displayed serum urea nitrogen levels of 223 +/- 9.5 mg/dl as compared to 26.0 +/- 1.0 mg/dl in sham-treated rats. This increment was significantly attenuated in acutely uremic, adrenalectomized animals (176 +/- 6.0 mg/dl). When these rats were substituted with corticosterone (5 mg/kg body weight), serum urea nitrogen readily increased to levels of acutely uremic animals with intact adrenal glands (225 +/- 6.0 mg/dl). The net generation of urea, as determined by the urea N appearance, was significantly increased during acute uremia (370 +/- 26 mg/48 h) as compared to SHAM animals (220 +/- 15 mg/48 h). This increment of urea formation could almost be completely reversed by simultaneous adrenalectomy (238 +/- 20 mg/48 h). When these rats were substituted with corticosterone, the urea N appearance rebounded to values quite comparable to acutely uremic rats with intact adrenal glands (363 +/- 30 mg/48 h). To determine whether skeletal muscle proteins might serve as a source for the enhanced protein degradation in acute uremia, plasma levels of Nt-methylhistidine were measured. Bilaterally nephrectomized rats had Nt-methylhistidine values of 9.6 +/- 1.0 micrograms/ml. In acutely uremic rats without adrenal glands, Nt-methylhistidine levels were found to be significantly decreased (6.0 +/- 0.4 micrograms/ml).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

PubMed1994

Changes in urinary excretion of endothelin-1-like immunoreactivity before and after unilateral nephrectomy in humans. Comparison with other urinary parameters and unilateral adrenalectomy.

To assess the value of endothelin-1 (ET-1) as a parameter of renal functional overload and the process of hyperfiltration, urinary excretion of ET-1-like immunoreactivity (U-ET-1) and urinary excretion of other parameters [beta 2-microglobulin (beta 2-MG), N-acetyl-beta-D-glucosaminidase (NAG), albumin (Alb) and 24-hour creatinine clearance (Ccr24)] were measured before, 1, 2 and 7 days after unilateral nephrectomy in 15 patients with unilateral renal lesions (renal cell cancer, renal pelvic cancer, ureteral cancer and renal tuberculosis) and after unilateral adrenalectomy in 5 patients with adrenal lesions. In the nephrectomy group (NX), Ccr24 significantly decreased at 1 and 2 days after the operation, but the other 4 parameters significantly increased after the operation as compared to preoperative values. In the adrenalectomy group (ADX), neither Ccr24 nor ET-1/Cr showed any change after the operation, but the other 3 parameters (beta 2-MG/Cr, NAG/Cr and Alb/Cr) significantly increased. Comparing the NX and ADX groups, both ET-1/Cr and beta 2-MG/Cr in NX were significantly higher than in ADX after the operation. On the other hand, neither NAG/Cr nor Alb/Cr in NX differed from values in ADX. Comparing ET-1/Cr and other parameters, only beta 2-MG showed a positive significant correlation. These results suggest that U-ET-1 may be an indicator of functional overload of the kidney.

Acetylglucosaminidase↗

PubMed1995

Regulatory effects of aerosolized budesonide and adrenalectomy on the lung content of endothelin-1 in the rat.

This study was designed to investigate the effect of inflammation and glucocorticosteroids (GCS) on the content of endothelin-1-like immunoreactivity (ET-LI) in the rat lung. Following intratracheal instillation of Sephadex beads, which induces a long-lasting inflammation in the lung, there was an increase in the lung content of ET-LI measured by RIA. This increase was abolished by locally administered aerosolized budesonide at doses that had only minor systemic effects (measured as a reduction in body weight). In a second series of experiments, rats were subjected to surgical adrenalectomy in order to reduce the levels of endogenous GCS. This procedure elevated the ET-LI levels in the lungs. In contrast, neither adrenalectomy nor high doses of budesonide administered systemically affected the concentration of ET-LI in the kidney. It is concluded that the lung ET levels are elevated in inflammatory conditions and that this increase is highly sensitive to locally administered GCS. Endogenous GCS may, directly or indirectly, play a role in the regulation of lung ET content but there seems to be no general GCS effect on basal tissue levels of ET.

Administration, Inhalation↗

PubMed1981

Pituitary response to bilateral adrenalectomy, metyrapone treatment and ether stress in the newborn rat.

ACTH level, determined by radioimmunoassay, has been used as a reliable test to investigate pituitary response to bilateral adrenalectomy, metyrapone treatment and ether stress in 8-day-old rat newborns. The pituitary gland able to enhance ACTH release significantly, first in response to the decrease in plasma corticosteroid levels induced either by bilateral adrenalectomy or by metyrapone inhibition of the corticosteroidogenesis, and second in response to 2 min of ether exposure. This latter response was greater in females than in males but smaller in neonates than in adults. These data suggest that the steroid-feedback mechanism was operating fully at the 8th postnatal day and that central mechanisms partially responded to external signals of stress. However, a relative 'stress-non-responsive period' was evident by the 8th postnatal day. The newborn rat's hypothalamic-pituitary axis has partially matured to be responsive to stress by the end of the first week after birth.

Adrenalectomy↗

PubMed1981

Effect of adrenalectomy on the transmission of IgG in young rats.

Antibody transmission in rats aged 17 days was unaffected by adrenalectomy performed at 13 days. The normal 'closure' of the jejunum to antibody is delayed by about 2 days in adrenalectomised rats. Adrenalectomy at 13 days has no apparent effect on plasma volume or haematocrit. Plasma corticosterone levels increase fivefold between 14 and 20 days, but in early weaned animals with 'closed' guts, corticosterone levels were not raised.

Adrenalectomy↗

PubMed1982

Development of bile acid biogenesis in the rat: effect of neonatal thyroidectomy, adrenalectomy, and streptozotocin-induced diabetes.

Effect of neonatal thyroidectomy, adrenalectomy and streptozotocin-induced diabetes in rats on the bile acid pool size and composition at weaning was examined. Adrenalectomy caused a significant (p less than 0.05) decrease in the total bile acid pool with significant reductions (p less than 0.05) in both cholic and chenodeoxycholic acids. Thyroidectomy on the other hand caused a specific decrease (p less than 0.05) in chenodeoxycholic acid pool. Streptozotocin-induced diabetes caused (a) a decrease (p less than 0.05) in total bile acid pool with a significant (p less than 0.05) reduction in chenodeoxycholic acid, and (b) an increase in plasma cholesterol levels.

Adrenalectomy↗

PubMed1989

Influence of adrenalectomy on the development of the neonatal thymus in the rat.

Adrenalectomy of 1-, 6-, 11- and 16-day-old male and female rats did not cause any changes in the weight of thymus 5 days later. Adrenalectomy on days 21, 26, 31 and 81 of age induced a significant hypertrophy of the thymus 5 days later. These results indicate that after about the time of weaning, the thymus is under some inhibitory regulation by the adrenal gland.

Adrenalectomy↗

PubMed1991

Effects of maternal bilateral adrenalectomy and betamethasone administration on fetal rat encephalic development.

The present study examined the effects of maternal bilateral adrenalectomy and betamethasone treatment on fetal encephalic development, in terms of fetal body weight, brain weight, DNA, protein and lipid content and morphological development. Both influenced the developmental time patterns of fetal brain and cerebellum. Fetuses of adrenalectomized rats had decreased body weights, whereas brain weight was not affected. Maternal adrenalectomy produces in fetal brain a decreased number of cells and increased cell size, while betamethasone treatment of adrenalectomized rats increased cell number, which was not different from control values; cell size remained lower than in control fetuses. Lipid content was increased in the fetuses of betamethasone-treated rats. In terms of morphological development, laminated structures (hippocampus and brain and cerebellar cortex) were the ones most affected.

Adrenalectomy↗

PubMed1989

Compensatory adrenal hypertrophy following unilateral adrenalectomy of fetuses of rats given alcohol throughout gestation.

The effect of maternal alcohol consumption on fetal compensatory adrenal hypertrophy following unilateral adrenalectomy was studied in rats. Females were given 20% alcohol in tap water for 4 weeks prior to mating and 30% alcohol in tap water throughout gestation (alcohol), or were pair-fed to the alcohol group (pair-fed) or were fed ad libitum (control). On day 20, fetuses were unilaterally left-adrenalectomized or sham operated. Mothers were sacrificed on day 22 of gestation and right adrenals of adrenalectomized, sham-operated, and unoperated fetuses were removed and weighed. Some adrenals were fixed, sectioned, and stained for histological examination. Adrenalectomized fetuses of all three dietary treatment groups demonstrated compensatory hypertrophy. Adrenals of alcohol-exposed fetuses weighed less than those of pair-fed or control fetuses, and the ratio of adrenal weight/body weight was greater, regardless of surgical procedure. Histological sections of right adrenals of left-adrenalectomized fetuses showed larger cells and widened sinusoids, compared to unoperated fetuses in the corresponding dietary treatment groups. These results are consistent with a retardation in adrenal growth and development as a result of alcohol exposure, but show that alcohol consumption throughout gestation does not affect the ability of the adrenals to undergo compensatory hypertrophy following unilateral adrenalectomy.

Adrenal Glands↗

PubMed1993

The technique of transperitoneal laparoscopic nephrectomy, adrenalectomy and nephroureterectomy.

In the traditional kidney position three trocars are inserted after creation of a pneumoperitoneum: 10 mm periumbilical (port I), 10/12 mm subcostal (port II) and 12/10 mm above the iliac spine (port III) in the mamillary line. After laterocolic incision the colon is dissected away from the lateral wall. Thereafter two 5-mm trocars (ports IV, V) are inserted into the lateral abdominal wall parallel to parts II and III. Following clipping and dissection of the ovarian (spermatic) vein, the ureter is isolated and incised. Then the cranial part of the ureter is used as a retractor exposing the renal hilum for dissection of the renal vessels. The main renal artery and vein are dissected separately by use of an endoscopic stapling device (Endo-GIA, white magazine). Finally, the kidney including Gerota's fascia is isolated from the adrenal and the upper peritoneum. Entrapment of the organ is performed with a specially designed bag (Lap-sac). The neck of the bag is brought out onto the surface of the abdomen (via port II/III) allowing digital morcellation with index finger inside the bag and removal of the organ in several pieces. We have applied this technique for 17 procedures in the upper retroperitoneum: 9 transperitoneal laparoscopic nephrectomies (TLN) for benign disease (5 hydronephrosis, 3 renovascular disease, 1 chronic pyelonephritis), 3 radical TLN including adrenalectomy for renal cell carcinoma (T2G2), 1 adrenalectomy for a cortical adrenaloma, 1 nephroureterectomy, 1 diagnostic ureterolysis and 2 modified retroperitoneal lymphadenectomies for stage I testicular cancer. The mean operation time was 4 h (2-5), the mean postoperative hospital stay 6 days (4-12).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenalectomy↗

PubMed1987

Effect of adrenalectomy on transport in the rat medullary thick ascending limb.

Previous studies in adrenalectomized (Adx) rats suggest that aldosterone may regulate ion transport in the ascending portion of Helen's loop. In order to examine directly the effect of adrenalectomy on transport, medullary thick ascending limb (Mtal) segments were isolated from Adx, Adx replaced with aldosterone (Adx + Ald, 0.5 micrograms X 100 g X body wt X d), and control Sprague-Dawley rats. Both net sodium and net chloride fluxes were significantly less in the Mtal segments from Adx rats compared with those in the control or Adx + Ald group. Physiologic levels of exogenous aldosterone increased net sodium chloride flux toward control values in the Adx + Ald group. Net potassium flux was not different among the three groups. We conclude that adrenalectomy impairs reabsorptive NaCl but not K transport in the Mtal, and that aldosterone restores this process. This reabsorptive defect may contribute to the urinary concentrating and diluting abnormality associated with adrenal insufficiency.

Adrenalectomy↗

PubMed1983

Adrenalectomy inhibits noradrenergic, adrenergic, and vasopressor responses to angiotensin II in the Pekin duck (Anas platyrhynchos).

The iv injection of Asp1, Val5-angiotensin II(AII) was followed by increases in arterial plasma norepinephrine (NE) and epinephrine (E) concentrations and elevation of arterial blood pressure in the anesthetized Pekin duck. AII injection did not affect the concentration of unconjugated dopamine in arterial plasma. Adrenalectomy inhibited the increases in plasma NE and E concentrations elicited by AII. Pressor responses to AII also were diminished after adrenalectomy, whereas pressor responses to exogenous NE and tyramine were not measurably affected. The alpha-adrenergic blocking drug phenoxybenzamine diminished the pressor effect of AII in both shamoperated and adrenalectomized ducks. The blockade of alpha-adrenergic receptors by phenoxybenzamine was incomplete, since pressor responses to exogenous NE were lessened by not abolished. We conclude from these experiments that AII increases arterial blood pressure in the Pekin duck by mobilizing NE and E from both adrenal and extraadrenal stores. It remains unknown whether the residual pressor response to AII in phenoxybenzamine-treated, adrenalectomized ducks involves an alpha-adrenergic mechanism.

Adrenalectomy↗

PubMed1985

Quantification of morphological changes in pituitary corticotropes produced by in vivo corticotropin-releasing factor stimulation and adrenalectomy.

Physiological and morphological changes produced by corticotropin-releasing factor (CRF) stimulation in vivo were studied in pituitaries immunocytochemically stained for ACTH. After 48-h ip minipump infusions of 10 or 50 ng/min CRF, serum ACTH levels were increased significantly over values in control groups that included both intact rats and rats exposed to sham abdominal surgery. Correlative morphological changes included a striking increase in corticotrope cell area. This was coupled with an apparent decrease in the percentage of stained cells, probably due to degranulation. The cellular responses were similar to those after adrenalectomy described previously by us and others. Therefore, in a parallel study, additional groups of rats were adrenalectomized and studied 24 and 48 h after the surgery. Even greater changes in serum ACTH, corticotrope cell area, and percentages were observed in the adrenalectomized rats. The difference between the CRF-infused and adrenalectomized groups was probably due to the lack of corticosterone feedback in the latter group. Among the control groups, there were no differences between intact rats and rats exposed to sham abdominal surgery. Rats subjected to sham adrenalectomy, however, showed corticotrope responses similar to those of CRF-infused rats, except that the cells were more densely stained. The present studies thus show dramatic changes in ACTH cell area, extent of staining, and percentages after in vivo CRF stimulation. In all of the experimental groups, an excellent correlation existed between serum ACTH levels and the degree of the morphological changes in the corticotropes.

Adrenalectomy↗

PubMed1987

Hypophysial-portal plasma levels, median eminence content, and immunohistochemical staining of corticotropin-releasing factor, arginine vasopressin, and oxytocin after pharmacological adrenalectomy.

Changes in immunostaining, median eminence content, and secretion into the hypophysial-portal circulation of immunoreactive CRF (irCRF), arginine vasopressin (irAVP), and oxytocin (irOT) were directly evaluated after pharmacological adrenalectomy (PHADX). Mean circulating levels of ACTH rose from 270 +/- 57 (+/- SE) to 1560 +/- 283 pg/ml after 72 h of treatment with metyrapone and aminoglutethimide. Initially, hypophysial-portal plasma irCRF levels decreased to 52.6% (12 h) and 21.7% (24 h) of control levels (230 +/- 41 pg/ml). Accompanying changes in the patterns of CRF immunostaining in the paraventricular nuclei (PVN) or in median eminence irCRF content at 24 h did not parallel alterations in portal plasma irCRF levels at this time. By 72 h posttreatment, portal irCRF levels were elevated 2.2-fold, while the number of detectable CRF-positive perikarya in the PVN increased 3.0-fold. The mean hypophysial-portal plasma irAVP concentration was unchanged from the control value (1312 +/- 287 pg/ml) at 12 h, but was only 34.9% of the control value at 24 h. Inverse changes in median eminence irAVP content were noted at these times, whereas the number of AVP-immunostained cells exhibited a tendency toward an increase at 24 h, in parallel with significantly increased content. By 72 h post-PHADX, portal irAVP, median eminence irAVP content, irAVP immunostaining intensity, and AVP-immunopositive cell number were elevated. Approximately 64% of CRF-positive perikarya in the parvocellular PVN costained for AVP at this time, whereas no colocalization was evident in untreated rats. These changes were prevented by corticosterone replacement. irOT staining intensity, irOT-positive cell number, median eminence irOT content, and portal plasma irOT concentration remained stable at all times examined. We conclude that: removal of adrenal steroids by PHADX results in a sequence of changes in CRF and AVP within the PVN (as determined by immunocytochemistry) and the median eminence (as determined by peptide content) similar to those observed after surgical adrenalectomy; after steroid removal the secretion of both irCRF and irAVP changes in a biphasic manner characterized by reduced secretion at 24 h and greatly enhanced secretion at 72 h; neither immunostaining nor median eminence content alone proved to be a reliable index or secretory activity during the initial phases of steroid blockade; and the hypophysiotropic OT system of normal male rats appears to be insensitive to adrenal steroid influences.

Adrenal Cortex Hormones↗