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N Inpanbutr

Publications and source records attributed to N Inpanbutr.

5 recordsLinked to original sources

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

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

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

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