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Biomedical subjects

M T Buckman

Publications and source records attributed to M T Buckman.

At least 37 records · Page 2Linked to original sources

Differential lipemic and proteinemic response to oral ethinyl estradiol and parenteral estradiol cypionate.

Oral synthetic estrogen administration to normal women has been shown to result in both a lipemic and a proteinemic response. To determine whether parenteral estrogen administration would have similar results, the effects of intramuscular depo-estradiol cypionate on serum lipids and ceruloplasmin were examined. The oral and parenteral estrogens chosen for this study are frequently used therapeutically and varying doses in the range of those commonly employed clinically were given to the experimental subjects. Following oral ethinyl estradiol (20, 50, and 100 micrograms every 12 hr) comparable and significant increases in triglyceride (73 +/- 6 to 128 +/- 10 mg/dl, p < .001), ceruloplasmin (87 +/- 4 to 188 +/- 11 mg/dl, p < .001), and HDL-cholesterol (60 +/- 2 to 74 +/- 3 mg/dl, p < .001) were observed. In contrast, despite substantial increases in serum estrogens, parenteral estrogen administration (depo-estradiol cypionate, 5 and 10 mg) failed to result in alterations in any of the measured parameters. Thus, the route and/or type of estrogen administered may determine the proteinemic and lipemic effects of estrogen in man.

Administration, Oral↗

Indomethacin fails to alter basal or phenothiazine-induced prolactin concentrations in man.

In order to evaluate the possible role of prostaglandins in pituitary prolactin (PRL) secretion, PRL was serially measured following perphenazine (Trilafon) ingestion in 8 men before and after 5 days of indomethacin administration. Since estrogens have been shown to modulate prolactin secretion in man, serum steroids including estrone (E1), estradiol (E2), progesterone (P) and testosterone (T) were measured before and after indomethacin ingestion. Serum E1, P and T levels were similar during the pre- and post-indomethacin study periods: 56 +/- 4 (1 SEM) vs 48 +/- 5 pg/ml, 298 +/- 28 vs 315 +/- 32 pg/ml, and 8.1 +/- 0.7 vs 8.6 +/- 0.7 ng/ml, respectively. Serum E2 levels were slightly, but significantly, lower following indomethacin treatment at 30 +/- 3 vs 37 +/- 3 pg/ml (p less than .01). Basal serum PRL concentrations were unaffected by indomethacin administration (9 +/- 3 pre- vs 8 +/- 2 ng/ml post-drug treatment). Integrated perphenazine-induced PRL responses were likewise similar during the 2 study periods: 101 +/- 16 ng . hr/ml during the control period and 104 +/- 14 ng . hr/ml following indomethacin. Thus, short-term indomethacin treatment had no effect on basal or perphenazine-stimulated PRL secretion in men.

Adolescent↗

Primary empty sella syndrome with visual field defects.

A patient with an enlarged, asymmetric sella turcica and visual field defects suggestive of a pituitary or parasellar tumor underwent extensive roentgenographic and pituitary function studies. No abnormalities in pituitary luteinizing hormone, follicle-stimulating hormone, thyroid-stimulating hormone, ACTH, prolactin or vasopressin secretion were detected. Growth hormone secretion was provoked by arginine infusion but not by hypoglycemia. Pneumoencephalography revealed air in the sella turcica, and no evidence of tumor. Thus, an enlarged sella turcica in a patient with visual field defects but normal pituitary function may suggest the presence of an "empty sella syndrome."

Humans↗

Hyperprolactinemia influences renal function in man.

Renal handling of solute and water following oral water loading was determined in six subjects with small pituitary adenomas associated with nonsuppressible hyperprolactinemia. Compared to control subjects, urine volume and solute excretion were significantly diminished in the hyperprolactinemic group. This was attributable to a decrease in osmolar clearance. Free water clearances were not different from control subjects. Hypothyroidism and adrenal insufficiency as an explanation for the antidiuresis were excluded in each patient. The data supports the suggestion that prolactin influences renal function in man.

Adenoma↗

Endogenous estrogen modulates phenothiazine stimulated prolactin secretion.

The role of endogenous estrogen in the regulation of serum prolactin concentration in man is controversial. To evaluate the possible effect of endogenous fluctuations in serum estrogen on the regulation of prolactin secretion, the authors determined phenothiazine stimulated prolactin secretion in 12 women in the early follicular phase of the menstrual cycle when estrogen levels were low (mean +/- SE E1 + E2 = 82 +/- 7 pg/ml) and compared it to the response during the late follicular phase when estrogen levels were higher (mean E1 + E2 = 320 +/- 63 pg/ml). Mean basal serum prolactin concentrations were similar in the early and late follicular phases of the cylcle (17 +/- 4 and 20 +/- 2 ng/ml, respectively). The integrated prolactin response following phenothiazine administration was significantly higher at mid-cycle (402 +/- 46 ng-hr/ml) than in the early follicular phase (317 +/0 46 ng-hr/ml, P less than .02). Thus, these studies suggest that endogenous estrogen secretion may play a role in the regulation of serum prolactin concentration in man.

Adult↗

Osmolar control of prolactin secretion in man.

To study the effect of changing serum osmolality on serum prolactin concentration 11 volunteers were given oral and intravenous hypotonic and hypertonic fluids. Mean serum prolactin fell to 10.5 percent of baseline after oral water loading and to 15 percent of baseline after intravenous hypotonic saline infusion. Conversely, mean prolactin rose to 417 percent of baseline after intravenous hypertonic saline administration. The correlation coefficient of simultaneously determined serum prolactin and osmolality was highly significant (P .001). Isoosmolar changes in extracellular fluid volume did not consistently affect the concentration of prolactin in the serum. Thus, prolactin may be involved in the physiologic regulation of osmolar balance and the kidney may be an important farget organ for prolaction.

Administration, Oral↗