Anterior pituitary function during surgical stress and convalescence. Radioimmunoassay measurement of blood TSH, LH, FSH and growth hormone

Increased atherothrombotic markers and endothelial dysfunction in steroid users

BACKGROUND

The use of androgenic anabolic steroids (AAS) may be associated with changes in atherothrombotic markers and endothelial function. The purpose of this study was to compare atherothrombotic markers and endothelial function of AAS users and non-users.

DESIGN

Cross-sectional study.

METHODS

Ten athletes who were users of AAS (confirmed by urine analysis) and 12 non-user athletes were evaluated. Body weight, blood pressure, exercise load (hours/week), complete blood count (CBC), platelets, fibrinogen, lipids, high-sensitivity C-reactive protein (hs-CRP), follicle-stimulating hormone, testosterone and estradiol were measured. Endothelium-dependent and independent functions were assessed by brachial artery ultrasound.

RESULTS

AAS users had higher body mass and blood pressure (p < 0.05). Platelet count was higher whereas HDL-cholesterol was lower in AAS users compared with non-users (p < 0.05). Levels of hs-CRP were higher in AAS users (p < 0.001). Follicle-stimulating hormone was suppressed in all users and not suppressed in non-users (p < 0.001). Compared with non-users, flow-mediated dilation was significantly reduced in AAS users (p = 0.03), whereas endothelium-independent function was similar in both groups. Additionally, flow-mediated dilation was positively associated with levels of HDL- cholesterol (r = 0.49, p = 0.03).

CONCLUSIONS

AAS users present important changes in blood lipids as well as in inflammatory markers, which are compatible with increased cardiovascular risk. Furthermore, this profile is accompanied by a reduction in the endothelial function.

Hyperprolactinemia after laparoscopic ovarian drilling: an unknown phenomenon

BACKGROUND

The effects of ovarian drilling on the serum levels of gonadotropins and androgens have been studied previously. The aim of this study is to evaluate the effects of ovarian drilling on the serum prolactin levels and its relation to ovulation in women with polycystic ovary syndrome.

METHODS

This is a prospective controlled study. Thirty-six women with PCOS underwent ovarian electrocauterization in university hospitals. Control group consisted of 35 ovulatory women with unexplained infertility. Hormonal assessment performed in early follicular phase of spontaneous or induced cycle before operation in the two groups and repeated one week after operation. Hormonal assay was also performed in the early follicular phase of the first post-operative menstruation, folliculometry and progesterone assay were also performed in the same cycle. Data were analyzed by "repeated measurement design, discriminant analysis, correlation coefficient, and Fisher exact test".

RESULTS

Six to ten weeks after operation the serum mean +/- SD prolactin levels increased from 284.41 +/- 114.32 mIU/ml to 354.06 +/- 204.42 mIU/ml (P = 0.011). The same values for the control group were 277.73 +/- 114.65 to 277.4 +/- 111.4 (P = 0.981) respectively. Approximately 45% of subjects in PCOS group remained anovulatory in spite of decreased level of LH and testosterone. Prolactin level remained elevated in 73.2% of women who did not ovulate 6-10 weeks after the procedure.

CONCLUSION

Hyperprolactinemia after ovarian cauterization may be considered as a possible cause of anovulation in women with polycystic ovaries and improved gonadotropin and androgen levels. The cause of hyperprolactinemia is unknown. Hormonal assay particularly PRL in anovulatory patients after ovarian cauterization is recommended.

Recombinant cell ultrasensitive bioassay for measurement of estrogens in postmenopausal women

A recent analysis of data from nine studies provided convincing evidence that plasma estradiol measurements predict the risk of breast cancer in normal postmenopausal women. However, the median values detected by the various assays used in this study varied by 5-fold. These and other published data in normal postmenopausal women suggest that assays measuring low plasma estradiol concentrations suffer from problems of sensitivity, specificity, and precision. Availability of a practical, low-cost, specific, precise, and ultrasensitive estrogen assay might allow enhanced prediction of the risk of breast cancer and provide an objective means of selecting postmenopausal women for breast cancer prevention. A recombinant cell ultrasensitive bioassay (RCUB) for estrogen was recently validated for use in prepubertal children. We postulated that the RCUB might also prove useful for measurement of postmenopausal levels and designed the present study to examine this possibility. Thirty normal postmenopausal volunteers provided blood samples for measurement of estrogen by RCUB and, for comparison, by RIA. The estrogenic activity measured by RCUB [mean +/- sd, 11.9 +/- 10.9 pmol/liter (SI units, 3.23 +/- 2.96 pg/ml] was significantly lower than estradiol levels measured by RIA [43.7 +/- 44.0 pmol/liter (11.9 +/- 12.0 pg/ml)] in our volunteer subjects (P < 0.00001). Nonetheless, plasma estradiol levels measured by bioassay were significantly correlated with the estrogenic activity measured by RIA (r = 0.84) and by gas chromatography/tandem mass spectrometry (r = 0.85). To obtain biological evidence of the validity of the RCUB, we related plasma estrogen levels to body weight and body mass index and found highly significant correlations (r = 0.54 and r = 0.53, respectively). Surprisingly, 28 of 30 postmenopausal women were found to have estrogen levels in the prepubertal range with the RCUB. The levels detected by RCUB were similar to those previously reported using an ultrasensitive but less practical yeast bioassay. These results provide validation for the RCUB in postmenopausal women and suggest that it might prove useful for selection of women for drug therapy to prevent breast cancer.

Effects of ropivacaine infiltration on cortisol and prolactin responses to postoperative pain after inguinal hernioraphy in children

BACKGROUND/PURPOSE

Painful interventions may have a serious adverse psychological impact, particularly in young patients. Inguinal hernia repair is the most common surgical outpatient procedure performed on infants and children. The aim of this study was to compare the effects of pre- and postincisional infiltration of the surgical area with ropivacaine on cortisol (C) and prolactin (PRL) release and postoperative pain in children undergoing inguinal hernia repair.

METHODS

Forty-five school-age children, aged 6 to 10 years, undergoing outpatient inguinal hernia repair under general anesthesia were placed randomly into 3 groups. Preincisional wound infiltration of 3 mg/kg ropivacaine was performed in group I patients before surgery. Postincisional wound infiltration was performed in group II patients after hernia repair but before skin closure, and group III patients (controls) did not received any local anesthetic. In the postanesthesia care unit (PACU), objective pain assessments were performed every 5 minutes using a standardized 10-point objective pain scale.

RESULTS

Plasma C concentrations increased at the end of the operation in all groups but significantly only in the control group (P <.001). There was no significant difference between the pre- and postincisional groups with regard to pre- and postoperative C alterations (P >.05). Although plasma PRL concentrations increased significantly at the end of the operation in the control group (P <.001), no significant difference was found between pre- and postoperative values in the infiltration groups (P >.05). The pre- and postoperative plasma PRL differences were significant between only groups I and III (P <.001).

CONCLUSIONS

The findings of the current study suggest that wound infiltration with ropivacaine decreases the stress response to surgery and the postoperative pain.

Does stress influence ampicillin concentration in serum and tissues?

Exercise produces changes of drug levels in plasma and increases the concentration of free fatty acids (FFAs), which may interfere with drug-protein binding. FFAs seem to play an antagonistic role to drugs since they have a strong binding capacity to serum albumin. The aim of this study was to evaluate the influence of the consecutive exercise-induced stress in ampicillin levels. Two groups of Wistar rats were used. Group A consisted of six subgroups that were subjected to cold swimming (4 degrees C) for 5, 10, 15, 20,25, 30 days respectively. Group B was the control group. The animals were injected im. with ampicillin (1 g/Kg/8h in 5 doses). Results showed that exercise enhanced stress parameters (FFAs, adrenal weight, Ht%) and led to an ampicillin increase in all experimental groups comparatively to controls.

Iodine absorption after intraoperative bowel irrigation with povidone-iodine

PURPOSE

Povidone-iodine is a commonly used intrarectal tumoricidal agent in patients undergoing colorectal surgery. The aim of this study was to assess systemic absorption of total iodine and its effect on thyroid function after intrarectal application.

METHODS

Twenty patients with carcinoma of the rectum received intraoperative irrigation with either povidone-iodine (Group A; n = 10) or physiologic saline (Group B; n = 10). Ten patients with carcinoma of the sigmoid colon (group C) were treated the same as Group A. Electrolyte, total iodine, triiodothyronine, thyroxine, and thyroid-stimulating hormone values were measured in serum preoperatively and before intraoperative irrigation and immediately, ten minutes, 1 hour, 6 hours, 24 hours, and two weeks after irrigation.

RESULTS

No significant changes occurred in serum electrolytes. A significant uptake of the total iodine was demonstrated in each group. Total iodine levels examined immediately, ten minutes, and one hour after irrigation in Group C were significantly higher than those examined in Group B. Maximum values were obtained one hour after irrigation in Groups A and B and six hours after irrigation in Group C. No significant changes occurred in triiodothyronine, thyroxine, and thyroid-stimulating hormone levels among the three groups. The decrease in triiodothyronine levels after surgery was demonstrated in each group. We noted a decrease after surgery in thyroxine levels for Groups A and B and in thyroid-stimulating hormone levels for Group B. Those hormones were not affected by the administration of povidone-iodine.

CONCLUSION

High serum levels of iodine did not cause organ toxicity, suggesting that a single use of intraoperative bowel irrigation with povidone-iodine may be performed with practically negligible risk.

Recovery advantages of regional anesthesia compared with general anesthesia: adult patients

The data support but do not conclusively prove, that RA results in a superior recovery compared with GA. However, several questions need to be answered. Even though the patient may leave the hospital or surgicenter sooner after RA, how does the patient treat pain at home once the block has "worn off"? Since short-acting sedatives and opioids are so commonly used with RA, to what extent is recovery due to them and to what extent is recovery due to the RA alone? Many of the studies examining beneficial effects of RA have been poorly conducted, combining RA with GA and producing inconclusive results. Anesthetic techniques need to be carefully compared to determine whether they are equal in quality, efficiency, and cost. Finally, to determine whether RA is cost-effective, future studies involving ambulatory patients with a focus on outcome and well-being need to be conducted.

Neuroendocrine stress response after minimally invasive surgery in pigs

Minimally invasive operations such as laparoscopic cholecystectomy appear to result in more rapid recovery of normal function, less physiological disturbance, and presumably less stress to the organism than open operation counterparts. The purpose of this study was to determine the stress response associated with minimally invasive surgery compared to conventional laparotomy. Three groups of pigs underwent general endotracheal anesthesia. The first group had laparoscopic cholecystectomy, the second open cholecystectomy, and the last group (controls) had only general anesthesia. The neuroendocrine serum stress markers adrenocorticotropic hormone (ACTH), cortisol, insulin, and glucagon were measured prior to anesthesia and for the first 3 postoperative days. Analysis of the data showed significant elevations of both ACTH and cortisol for laparoscopic operations as well as for open operation (cortisol only) in the immediate postoperative period. No differences were found for the other serum stress markers. We conclude that minimally invasive surgery in this porcine model confers no advantage, as measured by four neuroendocrine stress hormones, over conventional surgery. Further study is required to determine the clinical implication of these findings.

Acute development of low T3 syndrome and changes in pituitary-adrenocortical function after elective cholecystectomy in women: some differences between young and elderly patients

From two groups of female patients (young group: 15 patients aged less than 25 years; elderly group: 15 patients aged more than 65 years) who were subjected to cholecystectomy, blood samples were obtained on the day before surgery, on the day of surgery before premedication and after waking up from anaesthesia and also on days 1, 3 and 7 after surgery. In aliquots of sera the levels of TSH, ACTH, thyroxine (T4), triiodothyronine (T3), reverse triiodothyronine (rT3) and cortisol were estimated with the aid of radio-immunoassay (RIA). The differences between the young and elderly subjects were evaluated with the aid of four different statistical tests. Though no changes in the level of T4 were found, the level of T3 was significantly decreased and that of rT3 was significantly increased on Day 1 after surgery. However, the decrease of T3 was expressed more significantly in the young group and, in addition, an increase of rT3 in the same group was found even before premedication. The level of TSH showed a sharp increase at the end of surgery, which was expressed more in the young group. Though no differences between groups were observed in a sharp peak of the ACTH level during surgery, the increase of cortisol level in the elderly group was significantly higher and remained so during the post-operative period.

Abnormalities of the hypothalamo-pituitary-gonadal axis after head injury

OBJECTIVE

We aimed to investigate the mechanisms of hypogonadism which develops after head injury.

DESIGN

Pulsatile secretion of LH was studied in subjects 6-10 days after major head injury.

PATIENTS

We studied five male subjects admitted with major head injuries and six healthy age-matched control subjects.

MEASUREMENTS

During the pulsatility study, LH was measured at 5-minute intervals for 4 hours and 15-minute intervals for a further 2 hours. In addition, testosterone and LH were measured on Days 1-5, 14 and after 3-6 months.

RESULTS

The analysis of pulsatile secretion of LH demonstrated an LH pulse frequency similar to control subjects, but a significantly reduced LH pulse amplitude (P less than 0.001, fixed threshold method; P less than 0.02, Detect method). Both testosterone and LH levels were reduced after injury with the nadir occurring on Day 4.

CONCLUSIONS

Hypogonadism after head injury is due to defective LH secretion, with normal pulse frequency but a reduced pulse amplitude.

Haemodynamic and neurohumoral effects of xenon anaesthesia. A comparison with nitrous oxide

Thirty-two patients were randomly allocated to be anaesthetised either with nitrous oxide or xenon. Those who received nitrous oxide required significantly more fentanyl peroperatively. Arterial blood pressure and heart rate were adequately controlled during surgery in both groups. Plasma noradrenaline and prolactin increased peroperatively in both groups, but plasma adrenaline and cortisol, which increased in the nitrous oxide group, did not change in the xenon group. Growth hormone was below control in those given xenon, but not in the nitrous oxide group, while dopamine remained unchanged in both groups. Postoperative plasma concentrations of noradrenaline, adrenaline, cortisol and prolactin (in both groups) and dopamine (in the nitrous oxide group) were elevated, and slowly returned to control. No differences were seen between the two gases in effects on plasma sodium and potassium. Xenon, because of its favourable haemodynamic, neurohumoral and antinociceptive properties, deserves a more prominent place in anaesthetic practice than it has so far occupied.

Retinal laser photocoagulation in diabetic patients causes prolactin, growth hormone and cortisol release

Stress of many kinds (psychological, physical, metabolic) is able to induce endocrine modifications in humans, such as growth hormone (GH), prolactin (PRL), luteinizing hormone (LH), glucagon and cortisol release. Argon laser photocoagulation of the retina (RP), the treatment of choice for diabetic retinopathy, is a painful and stressful maneuvre and represents a direct injury onto a nervous tissue. Therefore it was decided to evaluate the possible endocrine modifications induced by RP in diabetic patients affected by retinopathy. In 19 insulin-dependent diabetic patients (12 men and 7 women), RP induced cortisol release in all cases, GH and PRL release in men, but not in women, and no modification of LH and glucagon plasma levels; in 12 similar patients receiving saline infusions without RP, no endocrine modifications were observed. It is concluded that RP elicits GH, PRL and cortisol release in diabetic patients.

Determination of intraoperative plasma catecholamine concentrations using liquid chromatography with electrochemical detection

Liquid chromatography with electrochemical detection was used for the determination of norepinephrine and epinephrine in human plasma samples obtained prior to, after, and six times during the course of spinal fusion surgery for the correction of scoliosis. The catecholamines were extracted from plasma by alumina adsorption and chromatographed isocratically using a reversed-phase, ion-pairing system. Data obtained are compared to those obtained intraoperatively by other authors using a radioenzymatic method, and the mechanism of sympathetic activation during surgery is discussed. Preliminary data using 3-micron particle size columns and dual-parallel electrochemical detection are presented.

Prolonged follicular phase and depressed gonadotrophins following hysterectomy and corpus lute-ectomy in women with premenstrual tension syndrome

In an attempt to obtain further information on the aetiology of premenstrual syndrome (PMS), the endocrine changes following enucleation of the corpus luteum in the mid-luteal phase of the cycle were studied in seven patients with PMS, and the results compared to details of seven control patients undergoing hysterectomy for menstrual problems. In the luteal phase, before surgery, the concentration of progesterone and FSH was lower, while that of oestradiol was slightly higher, in women with PMS. Following enucleation of the corpus luteum, follicular development and ovulation recommenced more slowly in women with PMS compared to controls (time to ovulation: 21 (range 18-24, vs 19(14-20) d, P less than 0.01). During the follicular phase there was no difference between the two groups in the concentration of oestradiol. The rise in concentration of FSH following enucleation was delayed in patients with PMS, and the serum FSH concentration was significantly lower during the late follicular phase of the cycle, but not during the mid follicular phase. The results suggest that these women with PMS have a more sensitive 'feed-back' than the controls, resulting in a lower preovulatory FSH level even though the oestradiol levels were not different. The results also suggest that the abnormalities described during the preoperative luteal phase are associated with the delay in the initial FSH rise.

Alterations of neuroendocrine functions in spinal cord injury

A transverse myelopathy causes a marked dysfunction in the negative feedback of some of the hypothalamo-hypophyseal-target organ axes. Spinal cord injured (SCI) humans with lesions above T6 exhibit significantly lower serum LH and testosterone but not FSH. The parathyroid hormone-thyrocalcitonin regulation of bone metabolism is disturbed; the higher the lesion, the greater is the loss of mineral and matrix components of the bone. Further, the response to insulin induced hypoglycemia is blunted in SCI with high lesions, and their basal levels of norepinephrine, epinephrine, and cortisol are significantly lower than those of controls. Distension of the bladder or rectum, however, produces marked release of norepinephrine and concomitant increase in sympathetic activity. The results suggest impaired hypothalamo-hypophyseal-testicular, -adrenocortical, - adrenomedulary, -sympathetic axis dysfunction.

Neuroendocrine alterations in systemic disease

Systemic disorders clearly may exert a significant influence on neuroendocrine function. Disorders that cause significant stress to the body, either physical or psychological, may cause a resetting upward of the HPA axis to provide sufficient cortisol to counteract the stress and to help sustain energy substrate levels. GH levels also increase in many of these situations, again promoting sufficient energy substrate levels. In some circumstances the concomitantly low somatomedin activity may be speculated to be adaptative to prevent the insulin-like agonist activity of these substances as well as to prevent energy expenditure in body growth. However, in other situations such as chronic renal failure and cirrhosis, the decreased somatomedin activity may be primary, causing decreased feedback at the hypothalamic-pituitary level and increased GH levels. The stress-induced rise in PRL may also play a minor role in preserving energy substrate since high levels may promote insulin resistance. In most illnesses the 'euthyroid sick syndrome' develops. Whether such patients are 'euthyroid' or mildly hypothyroid is a matter of controversy. The fact that protein losses are increased during fasting when the lowered T3 levels are returned to normal with exogenous T3 supplementation suggests that these patients are indeed hypothyroid and this hypothyroidism serves to conserve energy substrate by decreasing the metabolic rate. The reproductive axis is often impaired with systemic illness. Again, teleologically this may be viewed as an inactivation of non-essential functions in times of stress. It would appear that the changes that occur with systemic illness, in general, are favourable to the organism in that they promote survival. The detailed neurotransmitter and hypophyseotrophic hormone changes resulting in the alteration in pituitary function remain to be elucidated for the most part.

Metabolic effect of glucose, insulin and potassium cardioplegia

Glucose-insulin-potassium (GIK) solution is widely used as a cardioplegic infusate for myocardial protection during aortic cross-clamping, to obtain rapid diastolic arrest and preservation of energy stores. Nine male patients with aorto-coronary bypass grafting procedure were studied with regard to the metabolic influence of GIK cardioplegia. Hyperglycemia was induced by the infusion of GIK solution for one week after surgery. The serum level of non-esterified fatty acid was high for one week while the triglyceride level was maintained at a high level only in the early post-operative period. Insulin, glucagon and growth hormone which influence carbohydrate and lipid metabolism were also elevated for one week after infusion of GIK solution. We conclude that the derangement of carbohydrate and lipid metabolism which is provoked by the use of GIK cardioplegia normalizes within two weeks after operation.

Effect of growth hormone on oral glucose tolerance and circulating metabolic fuels in man

We infused growth hormone into normal subjects in doses that raised circulating hormone to levels (30-35 ng/ml) similar to those seen during stress. Growth hormone excess failed to alter fasting glucose and somatomedin concentrations. However, non-esterified fatty acids and ketones increased by 50% (p less than 0.05) and 120% (p less than 0.01), respectively, despite 35% higher plasma insulin concentrations. When oral glucose was ingested 5 h after initiating the growth hormone infusion, plasma glucose rose by 2-2.5 mmol/l above control (saline infusion) values and the area under the glucose curve increased twofold (p less than 0.005). This occurred in the face of twofold higher insulin levels and normal suppression of glucagon. Growth hormone also did not affect the hyperglycaemic response to a combined infusion of cortisol, glucagon and adrenaline, but accentuated the rise in non-esterified fatty acids, ketones, and insulin caused by these hormones. Our data suggest that growth hormone excess rapidly produces insulin antagonistic effects that may contribute to stress-induced glucose intolerance and lipolysis, even though fasting glucose levels remain unchanged.

Anterior pituitary, thyroid, parathyroid and adrenal responses to subtotal thyroidectomy in patients with Graves' disease

Changes in the serum levels of anterior pituitary, thyroid, parathyroid, and adrenal hormones following subtotal thyroidectomy in 31 patients with Graves' disease were investigated. In 14 patients, rapid ACTH tests were performed on the preoperative and the first, third, and seventh post-operative days. Remarkable differences were not seen with regard to the changes in anterior pituitary hormones or cortisol, compared to those seen during general surgery. As to the thyroid hormones, the serum level of triiodothyronine (T3) decreased markedly after surgery and fell to half that of the preoperative value on the first postoperative day. Thereafter, a low value of T3 was maintained during the early postoperative period. Unlike T3, the serum level of thyroxine (T4) decreased gradually until the 7th post-operative day. The levels of both epinephrine and norepinephrine increased transiently during surgery, but the serum level of norepinephrine increased again on the third postoperative day. In the postoperative period, almost half the number of patients showed an inadequate cortisol response to rapid ACTH tests. It is suggested that the unique responses, such as the rise in serum norepinephrine or an inadequate response of cortisol to ACTH, or hypocalcemia, after subtotal thyroidectomy in patients with Graves' disease is largely due to the rapid decrease of T3 in the hypothyroid state, as was noted during the postoperative period.

Psychosocial factors and psychophysiological mechanisms in the aetiology and development of cancers

Socio-cultural factors which may play a contributory role in the aetiology of cancer have been extensively investigated and it is well established that the incidence rates of different forms and sites of the disease are not equally distributed throughout the population. Social class, occupational, environmental and 'life-style' differences, amongst others, have been found to be associated with an excess risk of cancer, although the argument concerning the relative importance of these various factors remains a controversial one. It seems increasingly clear however, that there are large behavioural components which govern exposure to potential carcinogens and there is growing interest in the extent to which social and psychological demands may be associated with these agents or may operate as contributory factors in their own right. A number of early studies of psychological approaches to the study of cancer aetiology are reviewed from a methodological perspective. Much of the early work suffered from the problem that psychological characteristics of individuals who already had cancer were used to construct models concerned with aetiological factors. A number of the more recent studies which have attempted to overcome these difficulties are discussed. Tentatively, these later investigations suggest that two main groups of factors are related to an increased risk of cancer. First, the loss of, or lack of closeness or attachment to an important relation (often a parent) early in life, and second, the inability to express hostile feelings or more generally the abnormal release of emotion. Several psychophysiological mechanisms are reviewed which have attempted to account for the relationship between psychological disturbances and the onset of cancer, particularly the growing evidence which implicated a role for the immune system as a link between the central nervous system and disease processes.

Serum levels of cortisol, dehydroepiandrosterone, dehydroepiandrosterone sulphate, estrone and prolactin after surgical trauma in postmenopausal women

Changes in serum hormone concentrations induced by surgical trauma were studied by determination of cortisol, dehydroepiandrosterone (DHA), dehydroepiandrosterone sulphate (DHAS), estrone (E1) and prolactin in 25 postmenopausal women. Blood samples were collected before, during and after mastectomy (14 women) and cholecystectomy (11 women). A slight peroperative increase in DHA preceded a marked postoperative decrease whereas no significant changes were seen concerning DHAS. The posttraumatic increase in cortisol values was delayed in relation to that of DHA, reaching its maximum on the first postoperative day. There was a pronounced postoperative increase in estrone which was only slightly (r = 0.3) correlated to the concomitant changes in the serum levels of DHA and cortisol indicating that other factors than increased availability of precursor steroids might influence this change. Prolactin levels showed an about fourfold peroperative increase and were normalized on the first day after surgery. No significant differences in preoperative values were seen between the groups although generally more pronounced and retarded changes were seen after cholecystectomy than after mastectomy.

Rapid adaptation of pituitary responsiveness to TRH in the post-surgical state. The role of free T3

In eight clinically and biochemically euthyroid patients undergoing routine major non-thyroidal surgery preoperative and daily postoperative serum concentrations of total and free thyroid hormones were measured. Thyrotrophin-releasing hormone (TRH) tests were performed preoperatively and on the first 3 postoperative days. There was a significant fall in mean serum total and free triiodothyronine (T3) concentrations on the postoperative days and mean reverse T3 concentrations rose reciprocally. There was no significant change in mean basal thyroid-stimulating hormone (TSH) values, but there was a significant increase in the mean TSH-response to TRH on the first postoperative day. The mean TSH response than declined sequentially until day 3 while mean free T3 concentrations remained significantly depressed. Mean serum free thyroxine(T4)concentrations remained normal during the study. Intrapituitary conversion of T4 to T3 or other down regulatory mechanisms could explain this rapid adaptation of the pituitary axis.

Suppressive effects of surgical stress on circulating androgens during and after prostatectomy

Changes in circulating testosterone (T) and dihydrotestosterone (DHT) levels were investigated 2 days before and 2, 7, 30 and 60 days after retropubic prostatectomy in 28 patients with benign prostatic hypertrophy. Following operation the concentrations of both steroids declined and reached minimal levels 2 days after surgery. One month post-operatively testosterone had recovered to its pre-operative value, whilst the recovery of dihydrotestosterone to its pre-operative level required a minimum period of 2 months. These data indicate the need for careful interpretation of any androgen measurement following surgery.

Impact of acute surgical stress on anterior pituitary function in female subjects

The effects of acute surgical stress and the accompanying anesthesia on anterior pituitary function in female subjects was studied by means of frequent perioperative determinations of the circulating concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin (PRL), growth hormone (GH), and thyroid-stimulating hormone (TSH). No appreciable alteration in the circulating concentrations of either LH or FSH could be detected. In contrast, the levels of PRL and GH were found to be markedly increased during the perioperative period, with the increase in pRL invariably preceding any noticeable alteration in GH levels. In addition, perioperative PRL but not GH levels were significantly higher (p < 0.01) in patients undergoing a major surgical procedure, in contrast to a minor one. Finally, this study furnishes detailed evidence of a small but significant (p < 0.05) increase in TSH levels in patients undergoing a major surgical procedure. These data indicate that augmentation of pituitary secretion of three stress-related hormones, but not gonadotropins, occurs during surgical procedures.

Endocrine changes at operation under general anesthesia: reproductive hormone fluctuations in young women

This study investigated changes in peripheral serum estrogen (E), Progesterone (P), luteinizing hormone (LH), follicle-stimulating hormone, and prolactin (PRL) in 11 women of reproductive age undergoing a variety of operations under general anesthesia without compromise of ovarian vasculature. All hormone determinations were plotted in relation to the midcycle LH peak; eight women with cyclic ovulatory menses served as controls. The absolute value of E declined after surgery but did not reach statistical significance. P levels postoperatively were significantly lower following ovulation (P less than 0.01) on cycle days +1 through +5. Intraoperative and postoperative PRL values were significantly greater than those of control subjects (P less than 0.05). Aside from a transient intraoperative decline in LH, the pattern of gonadotropin secretion was similar to that of control subjects. The decline in peripheral ovarian steroid levels appeared to be independent of abdominal entry or pelvic manipulation. The evidence favors direct inhibition of ovarian steroidogenesis by (1) toxic effects of anesthetic agents or (2) stress-induced changes in other hormone levels, e.g., hyperprolactinemia.

Circadian rhythms of plasma cortisol in migraine

Diurnal rhythm of plasma cortisol, of psychological state, and of pain was measured for two days in 25 migraine patients and eight control subjects. Fourteen of the migraine patients and none of the controls displayed either consistently high plasma cortisol or an occasional aberrant peak. Abnormal psychological findings, particularly depression, were found in the Minnesota Multiphasic Personality Inventory only in migraine patients with abnormal plasma cortisol levels. Neither psychological abnormality nor pain seemed the single cause of elevation of plasma cortisol.

Adrenal-testis interaction in the stallion

The authors describe the short and long term effects of synthetic adrenocorticotrophin and of cortisol on peripheral plasma testosterone concentrations in 2 stallions. A single injection of either hormone temporarily raised plasma testosterone concentrations but repeated injection (twice daily for 5 days) depressed plasma testosterone concentrations. Cessation of treatment was followed by a rise in plasma testosterone to concentrations higher than those in the pretreatment period. These findings are briefly discussed.

Thyrotropin, free and total triiodothyronine, and thyroxine in serum during surgery

Changes in free and total thyroxine (T4), triiodothyronine (T3) and thyroid stimulating hormone (TSH) in serum were measured before, during, and for nine days after uncomplicated abdominal surgery in eight patients. The results showed a pronounced fall in total as well as in free T3 levels, amounting to 50% in both variables on the first postoperative day, and returning towards preoperative levels on the seventh and ninth day. Apart from an increase during surgery, free T4 levels were constant in the whole period despite a slight postoperative decrease in total T4. The TSH level fell about 80% within the first 24 postoperative h, but returned to the preoperative level thereafter. These results suggest a suppression of both T3 and TSH production during the pre- and early postoperative period.

Effect of surgical stress on pituitary-testicular function

The effect of surgical stress on the secretions of LH, FSH, testosterone (T) and oestradiol (E2) were studied in twelve male patients. During surgery LH rose significantly; post-operatively, LH fell but remained persistently elevated a week after operation. However, T and E2 fell progressively to a nadir on the second and fifth post-operative day respectively and remained suppressed. Serum FSH showed no significant change. Despite a post-operative decrease in sex hormone binding globulin (SHBG) binding capacity, non-SHBG bound T showed a decrease parallel to T. Multiple sampling studies showed that the secretions of LH were increased and that of T were decreased post-operatively. Following surgery, LH responses to LHRH were magnified, FSH and T responses showed no significant change when compared with the pre-operative responses. These data suggest that secretions of LH were increased during surgery. Following surgical stress, T and E2 concentrations were suppressed resulting in a compensatory elevation of LH concentrations.

Alpha-adrenergic control of growth hormone release during surgical stress in man

The mechanisms involved in the initial release of growth hormone (GH) during cholecystectomy have been studied after the administration of phentolamine in saline and in isotonic glucose, and after the administration of 10% glucose. Infusion of these substances was started 10 min before and terminated 30 min after skin incision. The serum GH levels 30 min after skin incision in a nontreated control group were raised to 14.4 +/- 1.0 ng/ml. The alpha-adrenergic blockade by phentolamine (20 mg during 40 min) regardless of whether administered in saline or in isotonic glucose inhibited GH response to surgery (4.3 +/- 2.1 ng/ml, or 2.2 +/- 0.4 ng/ml). The administration of 10% glucose (40 g during 40 min) led to a diminished response in some, but not in all the patients (6.2 +/- 1.2 ng/ml). It is concluded that the alpha-adrenergic mechanism participates in GH response to surgery.

The acute effect of hysterectomy on ovarian function

The acute effect of abdominal and vaginal hysterectomy on the ovarian production of estradiol-17-beta (E2) and progesterone (P) was studied in a group of patients undergoing hysterectomy for various gynecologic indications. Plasma levels of steroids as well as gonadotropins (FSH and LH) were measured by RIA. There was a significant but transient drop of plasma E2 during the follicular phase and of plasma E2 and P during the luteal phase, following hysterectomy. No significant variations in the steroid plasma levels were found in a control group of patients undergoing laparoscopy for diagnostic purposes. No changes were noted in either group in the plasma levels of gonadotropins. The changes seen appear to be related to the surgical manipulation in the ovarian region rather than to the type of hysterectomy performed or the stress of surgery.