Seasonal Variation of Serum Cholesterol and Thyroid Hormone Levels Associated with Hibernation in Indian Common Toad, Duttaphrynus melanostictus (Schneider, 1799)

Suman Pratihar, Jayanta Kumar Kundu

Abstract


In this study it was tried to investigate that the seasonal variation of thyroid hormone was associated with hypometabolism during the phase of hibernation in Indian common toad (Duttaphrynus melanostictus). The decline in thyroid hormone concentration had its behavioral and physiological response that leads to increase and sustain cholesterol level in serum, which seems to be the most important metabolite during the hibernating phase. So it may be inferred that reduced thyroid hormone is associated with metabolism depression and also help to shift the metabolism towards lipid.


Keywords


Duttaphrynus melanostictus; hypometabolism; serum cholesterol; thyroid hormone

Full Text:

PDF

References


Bolander F. F., Jr. (2004), Molecular Endocrinology. 3rd Edition, Acad. Press, California (USA).

Egeberg J. C. and Rosenkilde P. (1965), «Iodine uptake and ultrastructure of thyroid gland in the cold exposed toads, Bufo bufo», Gen. Comp. Endocrinol., 5, 673.

Kar A. and Chandola Saklani A. (1985), «Circulating thyroid hormone concentration in relation to seasonal events in the male Indian garden ligard, Calotes», Gen. Comp. Endocrinol., 60(1), 14 – 19.

Kowalczyk P. and Sotowska J. (2000), «Cha nges in thyroid hormones in the serum and the thyroid gland of hibernating frogs Rana temporaria», Gen. Comp. Endocrinol., 119(2), 172 – 180.

Kuhn E. R., Durras V. M., and Verlinden T. M. (1985), «Annual variations of thyroid reactivity following thyrotropin stimulation and circulation levels of thyroid hormones in the frog Rana ridibunda», Gen. Comp. Endocrinol., 57, 266 – 273.

Lowry O. H., Brough N. J. R., Farr A. L., and Randall R. J. (1951), «Protein measurement with the Folin phenol reagent», J. Biol. Chem., 193, 265 – 275.

Samyan S. (2004), «Thyroid hormone directly regulates cholesterol-7 α-hydroxylase (CYP7A) gene expression through a thyroid receptor binding site in the CYP7A promoter», due.vci edu/urop/symp2004-Sping/62 125 version 1.

Tasaki Y., Inove M., and Isii S. (1986), «Annual cycle of plasma thyroid hormone levels in the toad, Bufo japonicus», Gen. Comp. Endocrinol., 62(3), 404 – 410.

Tomasi T. E., Hallergen E C., and Tucker T. J. (1988), «Thyroid hormone concentration in Black bear (Ursus americanus). Hibernation and pregnancy effects», Gen. Comp. Endocrinol., 109(2), 192 – 199.




DOI: https://doi.org/10.30906/1026-2296-2009-16-4-253-255

Refbacks

  • There are currently no refbacks.