1.Studies on the Mechanism of Post-partum Amenorrhea: Pituitary-Ovarian Axis during Post-partum Amenorrhea in Lactating Women.
Kyungza RYU ; Kab Bum HUH ; Bock Ja BYOUN ; Hyun Mo KWAK
Yonsei Medical Journal 1981;22(2):137-144
The aim of this study is to evaluate pituitary-ovarian function at different postpartum periods during the lactational amenorrhea in order to understand the mechanism by which puerperal lactation is associated with a protracted period of amenorrhea and natural infertility. Ninety four lactating women and 119 lactating women with menstruation, aged between 21 and 38 years, volunteered for this study. The pituitary was relatively insensitive to LH-RH during the first 3 weeks following delivery. The recovery of FSH responsiveness to LH-RH occurred earlier than that of LH. Normal FSH response resumed in the 2nd week while the LH response, although not normal, started at the 3rd week postpartum. Pituitary responsiveness after the 5th week postpartum was similar to that occurring in normally menstruating women, except that FSH response was exagerated. Serum prolactin levels were elevated above 160 ng/ml until the 5th week postpartum and decreased to 84.2 ng/ml in the 6th week postpartum. It appears that at least one reason for anovulation during the first four weeks following delivery is the relative insensitivity of the pituitary to hypothalamic stimulation. Prolactin does not seem to modulate pituitary responsiveness to LH-RH. In order to clarify hormonal profiles during the lactational amenorrhea beyond the 5th week puerperium, serum levels of LH, FSH, prolactin, estradiol and progesterone were determined during different postpartum periods. Serum FSH and LH levels during 1-10 months postpartum were similar to basal levels seen during the normal menstrual cycle. Serum estradiol concentrations throughout 1-10 months postpartum, however, were significantly decreased as compared with the levels during the follicular phase of the normal menstrual cycle. Serum prolactin levels were elevated throughout 1-10 months postpartum in lactating amenorrhic women but decreased as the postpartum period lengthened. As compared with lactating amenorrhic women, lactating women with resumed menstruation showed a decrease in prolactin levels from 89.20 ng/ml to 51.39 ng/ml at 1-3 months, from 75.08 ng/ml to 49.99 ng/ml at 4-6 months, and from 54.73 ng/ml to 28.74ng/ml at 7-10 months postpartum. These results suggest that the apparent anovulation seen beyond 5th week postpartum during lactation was not due to pituitary insensitivity to LH-RH. Rather, prolactindependent mechanism interfering with cyclic activity may be operative during long term lactation.
Amenorrhea/etiology*
;
Female
;
Gonadorelin/pharmacology
;
Gonadotropins, Pituitary/secretion
;
Human
;
Lactation*
;
Ovary/physiology*
;
Pituitary Gland/physiology*
;
Pregnancy
;
Prolactin/physiology
;
Puerperium*
2.A study about the involvement of H-ras oncogene in acromegalic patients.
Seung Kil LIM ; Yi Hyun KWON ; Yoon Suk CHUNG ; Kwang Jin AHN ; Eun Jik LEE ; Kyung Rae KIM ; Hyun Chul LEE ; Kab Bum HUH ; Tae Seung KIM
Korean Journal of Medicine 1993;45(3):353-360
No abstract available.
Genes, ras*
;
Humans
3.Effects of cyclosporin A on sex hormone and estrogen receptor in male rat with special reference to cyclosporin A-induced osteoporosis.
Won Yeong SHIN ; Song Zhul LI ; Sang Su CHUNG ; Hyun Chul LEE ; Kab Bum HUH ; Sung Kil LIM
Yonsei Medical Journal 2000;41(1):61-67
The mechanisms of high turnover bone loss induced by Cyclosporin A (CsA) are not clearly understood. Deficiencies in sex hormones result in high turnover osteoporosis, and not only androgen but also estrogen plays an important role in maintaining bone mass in men. To study whether or not there are any changes in the levels of sex hormones, aromatization, and the expression of estrogen receptors in CsA-induced osteoporosis, we treated 39 rats with vehicle, low-dose CsA (5 mg/kg) and high dose CsA (15 mg/kg) for 28 days, and measured sex hormone levels by radioimmunoassay. Aromatase activities in ROS cells and 3T3-L1 cells were determined by measuring the conversion rate of 3H-androstenedione into 3H-estrone. ER and ER mRNA were measured by competitive RT-PCR in collected marrow cells and ROS cells. The levels of free testosterone in the serum in low-dose CsA-treated rats were unchanged, but the levels were significantly decreased in those treated with high-dose CsA as previously reported. The levels of total estradiol in the serum were significantly increased in the low-dose CsA-treated group (5 mg/kg) and were comparable to levels of the control group in the high-dose CsA-treated group (15 mg/kg). CsA increased the conversion of 3H-androstenedione to 3H-estrone in ROS cells, but not in 3T3-L1 cells. Meanwhile, CsA treatment did not change the rates of ER or ER mRNA expression in ROS cells or in collected bone marrow cells. In conclusion, CsA treatment decreased the level of free testosterone in the serum, but did not decrease the level of serum estradiol by enhancing aromatization. High-turnover osteoporosis induced by clinical dosage CsA treatment may not be caused by lowering the levels of circulating estrogen or by decreasing the expression of estrogen receptors.
3T3 Cells
;
Animal
;
Aromatase/metabolism
;
Bone Marrow Cells/metabolism
;
Cell Line
;
Cyclosporine/pharmacology*
;
Cyclosporine/adverse effects
;
Male
;
Mice
;
Osteoporosis/chemically induced
;
Rats
;
Rats, Sprague-Dawley
;
Receptors, Estrogen/metabolism*
;
Sex Hormones/metabolism*
;
Sex Hormones/blood
4.Retrospective Analysis of the Efficacy of Dapagliflozin in Patients with Type 2 Diabetes in a Primary Clinic in Korea
Sang Hyun PARK ; Young Ju CHOI ; Eun Jung RHEE ; Kab Bum HUH
Endocrinology and Metabolism 2019;34(1):70-79
BACKGROUND: We aimed to retrospectively analyze the efficacy of 10 mg dapagliflozin (DAPA), which is a sodium-glucose cotransporter-2 inhibitor, in Korean patients with type 2 diabetes who visited a primary diabetes clinic. METHODS: In total, 83 patients with type 2 diabetes, who received treatment with DAPA for the first time in a primary diabetes clinic between January 2015 and October 2015, were included in the study. The effect of DAPA in lowering glycosylated hemoglobin (HbA1c) levels was evaluated via chart review at 6 months follow-up. The patients were categorized into five groups according to add-on to or switched from other glucose-lowering agents: add-on to metformin (MET, n=10), add-on to MET+dipeptidyl peptidase 4 inhibitor (DPP4i, n=12), switched from sulfonylurea (SU, n=13), switched from DPP4i (n=11), and switched from thiazolidinedione (TZD, n=37). All the participants had already used MET for their regimen. RESULTS: Treatment with DAPA reduced HbA1c level by 1.2%±0.8%. Moreover, a significant decrease was observed in all subgroups: add-on to MET, −1.2%±0.7%; add-on to MET+DPP4i, −1.4%±0.8%; switched from SU, −1.4%±0.7%; switched from DPP4i, −0.5%±0.7%; and switched from TZD, −1.2%±0.9% (P<0.01). A significant decrease in body weight (−3.1±2.6 kg, P<0.001) was observed after DAPA administration. Estimated glomerular filtration rate and urine microalbumin were significantly decreased after 6 months of treatment with DAPA (−4.0±13.5 mL/min/1.73 m2, P=0.03; −23.6±45.9 mg/L, P<0.001). CONCLUSION: Treatment with DAPA, whether added to or switched from other glucose-lowering agents, significantly decreased HbA1c levels in Korean patients with type 2 diabetes who visited a single primary diabetes clinic. DAPA can be considered as an optimal second-line treatment for patients with type 2 diabetes, as supported by real-world evidence studies.
Body Weight
;
Diabetes Mellitus, Type 2
;
Dipeptidyl-Peptidase IV Inhibitors
;
Follow-Up Studies
;
Glomerular Filtration Rate
;
Hemoglobin A, Glycosylated
;
Humans
;
Korea
;
Metformin
;
Primary Health Care
;
Retrospective Studies