Author/Editor		Majdič, G; Vaillant, C; Pogačnik, A; Bavdek, SV
Title		Calcitonin- and somatostatin-positive cells in thyroid gland of pigs at different ages
Type		članek
Source		HISTOCHEMISTRY
Vol. and No.		Letnik 100, št. 6
Publication year		1993
Volume		str. 481-4
Language		eng
Abstract		Immunohistochemical studies were carried out on calcitonin-, somatostatin- and serotonin-reactive cells in newborn pigs and pigs at 3 weeks and 7 months old. The aim of these studies was to examine if the expression of various bioactive substances by parafollicular cells in the pig thyroid varied during development. The volume density of the follicular epithelium was nearly the same in newborn and 3-week-old piglets and significantly lower in 7-month-old animals. The volume density of calcitonin-positive cells, expressed as a percentage of the follicular epithelium density, was similar in young animals, being 12.10 percent and 13.03 percent in newborn and 3-week-old piglets, respectively. A small but significant increase to 14.40 percent was seen in 7-month-old pigs. Somatostatin-positive cells formed a much smaller population at all time points, but these also showed a significant increase with age (0.13 percent, 0.17 percent and 0.52 percent of follicular epithelium density in newborn, 3-week- and 7-month-old pigs, respectively). However the changes in the volume density of somatostatin-positive cells correlated inversely with thyroid activity, the density being highest when the activation index was lowest, suggesting that thyroid activity may be regulated by an increase in the synthesis of this inhibitory peptide. Serotonin-positive cells were extremely rare at all time points and their volume density was not calculated.
Descriptors		CALCITONIN SOMATOSTATIN THYROID GLAND AGE FACTORS ANIMALS, NEWBORN IMMUNOHISTOCHEMISTRY SEROTONIN SWINE THYROID GLAND