Luteinizing hormone depletes ascorbic acid in preovulatory follicles.

OBJECTIVE: The objective of the present studies was to determine whether luteinizing hormone (LH) depletes ascorbic acid in the preovulatory follicle. DESIGN: Controlled, prospective experimental study. SETTING: University-based research center. ANIMAL(S): Sprague-Dawley female rats. INTERVENTION(S): Follicular growth and ovulation were induced in immature rats by gonadotropin treatment. MAIN OUTCOME MEASURE(S): Analysis of ovary, follicle, and oocyte levels of ascorbic acid by colorimetric analysis and high-pressure liquid chromatography. RESULT(S): Ovarian ascorbic acid was maximally depleted (50%) within 2 h of LH treatment and was sustained for 8 h. Follicle ascorbic acid levels were unchanged 1 h after LH injection but were significantly reduced within 2 h (40%). Incubation of isolated preovulatory follicles for 3 h with hCG or with menadione (a generator of oxygen radicals) reduced ascorbic acid levels. Isolation of cumulus-enclosed or denuded oocytes depleted ascorbic acid to undetectable levels, but follicular ascorbic acid levels were only moderately depleted by isolation and incubation. Accumulation of ascorbic acid by oocytes was significantly enhanced by the presence of intact cumulus cells. CONCLUSION(S): Elevation of LH and the production of oxygen radicals deplete ascorbic acid in the preovulatory follicle.

Traditional surgical approaches to uterine fibroids: abdominal myomectomy and hysterectomy.

Abdominal myomectomy and hysterectomy remain the traditional treatment of large symptomatic uterine myomas. The preoperative indications for abdominal myomectomy or hysterectomy must be clearly evaluated and delineated avoid unnecessary intervention. There appears to be an increasing trend toward expectant management for asymptomatic uterine myomas. Women should consider the options of myomectomy and hysterectomy when their symptoms are severe enough to warrant intervention and the benefits of intervention outweigh the risks. The advantages and disadvantages of preoperative medical also must be addressed before intervention. The factors influencing the choice of therapy seem to be strongly dependent on both the patient and physician preferences. A clinical approach to abdominal myomectomy in patients with infertility and repetitive miscarriage has been presented in this chapter. The rapid development and use of minimally invasive innovations and adjunctive medical therapies has provided clinicians with a wealth of alternatives. A practical and cost-effective approach based on the data currently available have been presented; however, there remains a paucity of prospective randomized data to evaluate and compare the effectiveness and safety of these alternative treatments to abdominal myomectomy and hysterectomy. Future studies should help define the optimal candidates for traditional surgical treatment with abdominal myomectomy and hysterectomy.

Adrenal medullary regulation of rat renal cortical adrenergic receptors.

The role of the adrenal medulla in the regulation of renal cortical adrenergic receptors was investigated in renal cortical particulate fractions from control rats and rats 6 wk after adrenal demedullation. The specific binding of [3H]prazosin, [3H]rauwolscine, and [125I]iodocyanopindolol were used to quantitate alpha 1-, alpha 2-, and beta-adrenergic receptors, respectively. Adrenal demedullation increased the concentration of all three groups of renal adrenergic receptors; maximal number of binding sites (Bmax, per milligram membrane protein) for alpha 1-, and alpha 2-, and beta-adrenergic receptors were increased by 22, 18.5, and 25%, respectively (P less than 0.05 for each). No differences were found in the equilibrium dissociation constants (KD) for any of the radioligands. Plasma corticosterone and plasma and renal norepinephrine levels were unchanged, whereas plasma epinephrine was decreased 72% by adrenal demedullation (P less than 0.01); renal cortical epinephrine was not detectable in control or demedullated animals. Our results suggest that, in the physiological state, the adrenal medulla modulates the number of renal cortical adrenergic receptors, presumably through the actions of a circulating factor such as epinephrine.