Biomedical subjects
Publications and source records attributed to C Haldar.
The general plan of the development of the organ in Calotes versicolor in no way differs from that of Sphenodon and Lacerta. The lens of the parietal eye of Calotes appears at a comparatively later state of development than in Sphenodon and Lacerta. The papaphysis in the embryos of Calotes versicolor is a simple structure. Histologically all the structures resemble the wall of the brain from which they arose.
To date, the phenomenon of maternal transfer of hormones to the young is an enigma. The present study explains for the first time the maternal transfer of melatonin (MEL) to the young, affecting neonatal growth and sexual maturation. The suckling pups of MEL-treated mothers exhibited significant decreases in body, testicular, vas deferens (male pups), ovarian and uterine (female pups) weights and increases in pineal gland activity along with high plasma MEL levels. The plasma level of testosterone decreased significantly in male pups, while estradiol increased and progesterone decreased in female pups of MEL-treated mothers. These results clearly suggest that MEL could be transported from the mothers to their young postnatally via the milk in order to influence neonatal growth and sexual maturation. Our results support the earlier concept and show for the first time that MEL can be transported from the mother to the young either prenatally through the placenta or postnatally via the milk. Therefore, maternal MEL can act as a biological signal for neonatal growth and sexual maturation.
Chronohaematological study was performed on the blood of pinealectomized and sham-operated lizards over a 48 hrs. time scale. Pineal removal significantly inhibited leucocytopoisis, erythropoiesis and led to hypoglycemia, as evident from lowered circulating number of cells and level of glucose respectively. However existence of circadian rhythm in WBC, RBC and glucose level of sham-operated lizards was evident. Influence of pineal extirpation on chronohaemotology varied with time scale (Time X Pinealectomy P less than 0.01).