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N Inpanbutr

Publications and source records attributed to N Inpanbutr.

13 recordsLinked to original sources
PubMed2004

Effects of 1,25(OH)2D3, 25OHD3, and EB1089 on cell growth and Vitamin D receptor mRNA and 1alpha-hydroxylase mRNA expression in primary cultures of the canine prostate.

The aim of this study was to investigate effects of 1,25(OH)(2)D(3) (calcitriol), 25OHD(3), and EB1089 on cell growth and on Vitamin D receptor (VDR) mRNA and 1alpha-hydroxylase (1alpha-OHase) mRNA expression in normal canine prostatic primary cultures. Canine prostatic epithelial cells were isolated, cultured, and treated with vehicle (ethanol), calcitriol, 25OHD(3), and EB1089 at 10(-9) and 10(-7)M. The VDR was present in epithelial and stromal cells of the canine prostate gland. 1,25(OH)(2)D(3), 25OHD(3), and EB1089 inhibited epithelial cell growth at 10(-7)M compared to vehicle-treated controls [calcitriol (P < 0.01), EB1089 (P < 0.01), and 25OHD(3) (P < 0.05)]. Epithelial cells treated with calcitriol and EB1089 at 10(-7)M had slightly increased VDR mRNA expression (0.2-0.3-fold) at 6 and 12h compared to controls. There was no difference in 1alpha-OHase mRNA expression in epithelial cells treated with these three compounds. 1,25(OH)(2)D(3) and its analogs may be effective antiproliferative agents of epithelial cells in certain types of prostate cancer.

Animals↗
PubMed1998

Effects of photoperiod and age on secretory patterns of luteinizing hormone and testosterone and semen production in male domestic turkeys.

The objective of this study was to determine effects of photoperiod and age on the circulating concentrations of LH, testosterone (T), thyroxine (T4), and semen production in male turkeys. Male turkeys from 10 or 12 wk of age were maintained under either a long-day (LD) photoperiod of 16L:8D up to 35 wk (LL), or a short-day (SD) photoperiod of 6L:18D to 29 wk and then an LD photoperiod of 16L:8D up to 35 wk of age (SL). Plasma concentrations of both LH and T increased by 17 or 18 wk of age under both photoperiods, but higher levels were attained in the LL group prior to 29 wk of age. Both LH and T levels increased significantly within days in the SL group after the group was switched to LD at 29 wk of age. Higher levels of T4 were present in the LL group prior to sexual maturation. No differences were observed in T4 concentration between lighting treatments after sexual maturation. The LL group first produced semen at 20-22 wk of age, which was about 1 wk earlier than first semen production in the SL group. A significantly larger volume of semen was produced in the LL group at most ages. No further increase in semen production was observed in the first 6 wk after the SL group was switched to the LD photoperiod at 29 wk of age. Pulsatile patterns of LH and T were characterized by serial blood sampling at 13, 23, and 35 wk of age under both the LL and SL photoperiods. The baseline levels of both LH and T in male turkeys were influenced by age and photoperiod. However, pulse characteristics (numbers, duration, and amplitude) of LH did not change with age or lighting treatment, while pulse characteristics of T did change with age. We conclude that exposing male turkeys to an LD photoperiod from 10 or 12 wk of age advanced the age of sexual maturation and induced earlier increased concentrations of LH and T.

Aging↗
PubMed1996

Effect of vitamin D on testicular CaBP28K expression and serum testosterone in chickens.

Vitamin D is known to reverse infertility in male and female rats. This study was an investigation of the effects of vitamin D deficiency on calbindin-D28K (CaBP28K) and testosterone levels in male chickens. Chickens were raised from 1 day of age to 8 wk of age on a normal or a vitamin D-deficient diet. A radioreceptor assay showed that serum vitamin D levels were significantly higher in chickens fed a normal diet than in those fed a vitamin D-deficient diet. The morphology of the seminiferous tubules was not different between the vitamin D-replete and vitamin D-deficient chickens. Immunohistochemical studies revealed that CaBP28K was present in spermatogonia and spermatocytes of the seminiferous tubules. A few interstitial Leydig cells were positive for CaBP28K. RIA was used to quantify the amount of CaBP28K in the testes, which was threefold higher in chickens raised on a normal diet than in chickens raised on a vitamin D-deficient diet. Testosterone concentration in serum, determined by RIA, was not different between the two groups. Neither serum calcium nor phosphorus levels were different between the two groups. This investigation represents the first demonstration of the effect of vitamin D deficiency on CaBP28K expression in chicken testes. The results indicate that the decrease in testicular CaBP28K concentration was attributable to vitamin D deficiency despite normal serum testosterone and calcium levels in 8-wk-old chickens.

Animals↗
PubMed1995

Calbindin-D9k expression in the pregnant cow uterus and placenta.

Calbindin-D9k (CaBP9k) is a vitamin D-dependent, calcium binding protein first identified in the cytoplasm of the intestinal epithelial cell. Using biotin-streptavidin immunohistochemistry, CaBP9k was localized to the maternal caruncular epithelium, fetal chorionic epithelium, and trophoblastic binucleated cells of the bovine placenta. Within the maternal epithelium the intensity of staining increases from second trimester pregnancies to term pregnancies, indicating a higher intracellular concentration of CaBP9k in the epithelium at term. Luminal and glandular epithelium of the non-caruncular endometrium also stained positively for CaBP9k in all stages of pregnancy observed. No CaBP9k was identified within the stroma or myometrium of the pregnant cow uterus. The increased level of CaBP9k in the caruncular epithelium during the last trimester is hypothesized to be in response to the rising demand for calcium to aid in the mineralization of the fetal skeleton. CaBP9k may play a role in enhancing calcium transport across the placenta in cattle.

Animals↗
PubMed1994

CaBP9K levels during the luteal and follicular phases of the estrous cycle in the bovine uterus.

The expression of calbindin-D9K (CaBP9K) and calbindin-D28K (CaBP28K) genes in the reproductive system is well established for rodent and avian species, but not for domestic livestock. This investigation expanded the study of these proteins to include the bovine uterus and examined the levels of CaBP9K and CaBP9K mRNA in the nonpregnant bovine uterus during the estrous cycle. Immunohistochemical studies revealed that CaBP9K was present in all uterine glandular and luminal epithelial cells. In contrast, the closely related calcium binding protein CaBP28K was present in only one to two glandular cells in the samples examined. Neither protein was localized in the myometrium or in the stromal cells of the endometrium. RIA and dot blot hybridization were used to quantify the amount of CaBP9K and CaBP9K mRNA. The levels of both the protein and its mRNA were threefold higher during the luteal phase than during the follicular phase. RIA was also used to determine bovine uterine levels of 17 beta-estradiol and progesterone. Progesterone levels were higher during the luteal phase than during the follicular phase, while 17 beta-estradiol levels were higher during the follicular phase. This investigation represents the first characterization of CaBP9K gene expression in the bovine uterus. It demonstrated that the expression of CaBP9K and CaBP9K mRNA was greatest during the progesterone-dominated luteal phase of the bovine estrous cycle. These results indicated that CaBP9K may be involved in uterine glandular function during the luteal phase.

Animals↗
PubMed1994

Association between calbindin-D28K and oogenesis in ovaries of chicken embryos in vitro.

The left ovary of chicken embryos was removed and incubated in culture medium with a thymidine analogue, bromodeoxyuridine (BrdU), in vitro. In addition, fertile chicken eggs were injected with BrdU via the extraembryonic vessels and incubated for 24 hours. The ovaries were then processed for immunohistochemical localization of calbindin-D28K (a 28-kd vitamin D-dependent calcium-binding protein) and BrdU. Calbindin-D28K was detected in the germinal epithelium and in cells surrounding the oogonia and oocytes (future granulosa cells) of the embryonic chicken ovary. However, BrdU was observed in the nucleus of the oogonia and oocytes of the chicken embryonic ovaries. Comparison of the 2 adjacent sections, immunostained for calbindin-D28K and BrdU consecutively, indicated that BrdU, the marker for cell proliferation was not detected in calbindin-D28K-containing cells, namely, germinal epithelium and future granulosa cells, in the ovary of chicken embryos. These results suggested that calbindin-D28K-containing cells in the ovary were not in the process of cell division during the 24-hour incubation of chicken embryos.

Animals↗
PubMed1993

Expression of calbindin-D28k in developing and growing ovaries of chicken embryos.

Immunoreactivity for 28 kd vitamin D-dependent calcium-binding protein (calbindin-D28k) has been localized in the germinal epithelium and cells surrounding oogonia and oocytes (future granulosa cells) of developing and growing ovaries of chicken embryos. The protein first appeared prominently in the germinal epithelium of the developing left ovary in 8-day embryos. At the twelfth day of incubation, cells surrounding oogonia and oocytes reacted intensely for calbindin-D28k. The number and intensity of calbindin-D28k-containing cells increased in both types of cells as the embryos further developed. Calbindin-D28k remained in the germinal epithelium throughout the study period observed (up to 10 weeks). However, the protein was present transiently in the future granulosa cells. It gradually decreased after hatching, and was virtually absent from granulosa cells in a 10-week old chicken. Compared with the known process of onset of sexual development, these results indicated possible involvement of calbindin-D28k in the early phases of oogenesis in chicken ovaries.

Animals↗
PubMed1993

Immunocytochemical localization of type A influenza virus nucleoprotein in chicken kidney, using freeze substitution technique for tissue fixation.

Kidney tissues were removed from euthanatized mature White Leghorn chickens 4 days after IV inoculation with type A influenza virus. The kidney tissues were then fixed at -70 C, using a freeze substitution technique. Type A influenza virus nucleoprotein was readily detected in the nuclei and cytoplasm of the proximal and distal tubular epithelial cells by immunocytochemistry, and the sharpness of the immunomarker in the cells indicated minimal antigen migration during fixation and tissue section preparation. This tissue fixation technique also resulted in good preservation of cellular morphology. The freeze substitution technique of tissue fixation is an excellent alternative to cryostat-cut acetone-fixed tissue sections or conventional chemical fixation of paraffin-embedded tissues for in situ immunocytochemical localization of type A influenza virus nucleoprotein antigen.

Animals↗
PubMed1992

Expression of calbindin-D28k in developing and growing chick testes.

Calbindin, a 28-kDa vitamin D-dependent calcium-binding protein was localized immunohistochemically in developing and growing chick testes. The protein first appeared in the germinal epithelium of developing testes of the eight-day-old embryo and remained therein throughout development. Calbindin was not present in the germinal epithelium after hatching. Calbindin was next detected in the spermatogonia and spermatocytes of one-week-old and growing chick testes. Calbindin-positive spermatogonia and spermatocytes gradually increased in number and staining intensity as the seminiferous tubules further developed. A few interstitial Leydig cells were positive for calbindin from five-week-old and older chicks. Comparison of the time-course of appearance and increase in calbindin content in spermatogonia and spermatocytes with spermatogenesis in chickens suggests that calbindin may be involved in the mitotic process in spermatogonia and spermatocytes.

Animals↗
PubMed1989

Calbindin-D immunolocalization in developing chick thyroid: a light and electron microscopic study.

Antiserum to calbindin-D, a 28 KD vitamin D-dependent calcium binding protein, was used to localize the protein immunocytochemically in developing chick thyroid by both light and electron microscopy. The protein first appeared in future follicular cells of developing thyroid tissue from 8-day-old embryos. The number of calbindin-D-containing cells increased rapidly to a near-plateau level at day 10; this concentration was sustained until day 15, and then declined to an undetectable level just before hatching. The protein was distributed throughout organelle-free areas of the follicular cell cytoplasm and extended into the nucleus; it was not present in the follicular colloid. Comparison of the time course of changes in calbindin-D content with known differentiative changes taking place in follicular cells suggests that the protein may function in some yet to be determined mechanism related to normal development of the thyroid.

Animals↗
PubMed1987

Localization of calbindin-D28K in calcitonin containing cells of chick ultimobranchial glands.

Specific antisera raised against calbindin-D28K (CaBP), the vitamin D-dependent calcium-binding protein from chick intestine, was used to localize the protein in chick ultimobranchial glands (UB glands) by the peroxidase-antiperoxidase technique. CaBP was localized in secretory cells in the cell cords and in a few cells of the epithelium lining the follicles. It was not found in the fibroblastlike cells in the cell cords nor in islands of parathyroid tissue present in the UB gland. The immunomarker for CaBP was distributed throughout the cytoplasm and nucleus of the secretory cells. The same cells demonstrated a positive reaction in their cytoplasm when reacted with an antiserum specific for salmon calcitonin (CT), thus confirming the presence of CaBP and CT in the same UB-gland secretory cells. In other tissues, the presence of CaBP is regarded as an end-organ marker for actions of the vitamin D endocrine system. This novel demonstration of CaBP in UB-gland cells responsible for secretion of calcitonin suggests a direct effect of the vitamin D endocrine system on those cells in addition to an indirect effect through the stimulation produced by elevated circulating calcium levels.

Animals↗
PubMedDate not supplied

Effects of 1,25(OH)2D3, EB1089, and analog V on PTHrP production, PTHrP mRNA expression and cell growth in SCC 2/88.

BACKGROUND: We investigated the effects of 1,25(OH)2D3 and selected analogs on canine squamous carcinoma cells (SCC 2/88) and tested whether these compounds could effectively decrease proliferation, induce differentiation, and inhibit PTHrP production and PTHrP mRNA expression. MATERIALS AND METHODS: SCC 2/88 cells were cultured and treated with three substrates. The media were collected for PTHrP immunoradiometric assay. The cells were analyzed for DNA concentration and PTHrP mRNA expression by Northern blot analysis, involucrin by Western blot analysis and 1,25(OH)2D3-receptor (VDR) and PTHrP by immunohistochemistry. RESULTS: The SCC 2/88 cells were stained positively for VDR and PTHrP by immunohistochemistry. 1,25(OH)2D3 and its analogs inhibited cell growth and stimulated differentiation in a dose-dependent manner. All three substrate-treated groups had significantly increased PTHrP secretion at 10(-7) M. Cells treated with 1,25(OH)2D3 at 10(-7) M had 2- to 4-fold increased PTHrP mRNA expression at 12 and 24 hours compared to the vehicle-treated controL PTHrP mRNA in cells treated with TGF-beta (1.5 ng/ml) was increased 7- to 17-fold at 6, 12 and 24 hours compared to the vehicle-treated controL PTHrP mRNA expression was reduced by 0.5- to 2-fold in cells treated with 1,25(OH)2D3 at 10(-7) M and TGF-beta (1.5 ng/ml) together compared to cells treated with TGF-beta alone. CONCLUSION: 1,25(OH)2D3, EB1089, and analog V inhibited SCC 2/88 growth and induced differentiation in a dose-dependent manner, but did not inhibit PTHrP production. 1,25(OH)2D3 treatment led to increased PTHrP mRNA expression and reduced the stimulatory effect of TGF-beta on PTHrP mRNA expression in SCC 2/88 cells.

Animals↗