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The mountainous Western Ghats are part of a biodiversity hotspot and extend for about 1600 km, lying close and subparallel to the west coast of peninsular India. The region is a centre of diversity for amphibians, and recent preliminary work on some components of both caecilian (Gymnophiona) and frog (Anura) fauna is indicative of a high degree of local endemism. We investigated diversity in mitochondrial rRNA 12S and 16S sequences for long-tailed, unstriped Ichthyophis (Amphibia: Gymnophiona: Ichthyophiidae) that potentially represent four taxonomically confused and poorly known endemic caecilian species. Data were analysed for18 individuals from along c.

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Though much is known about various aspects of reproductive biology of amphibia, there is little information on the cellular and mechanistic basis of assembly of ovarian follicles in this group. This is especially true of the caecilians. Therefore, taking advantage of the abundant distribution of caecilians in the Western Ghats of India, two species of caecilians, Ichthyophis tricolor and Gegeneophis ramaswamii, were subjected to light and transmission electron microscopic analysis to trace the sequential changes during the assembly of ovarian follicles. The paired ovaries of these caecilians are elongated sac-like structures each including numerous vitellogenic follicles. The follicles are connected by a connective tissue stroma. This stroma contains nests of oogonia, primary oocytes and pregranulosa cells as spatially separated nests. During assembly of follicles the oocytes increase in size and enter the meiotic prophase when the number of nucleoli in the nucleus increases. The mitochondrial cloud or Balbiani vitelline body, initially localized at one pole of the nucleus, disperses through out the cytoplasm subsequently. Synaptonemal complexes are prominent in the pachytene stage oocytes. The pregranulosa cells migrate through the connective tissue fibrils of the stroma and arrive at the vicinity of the meiotic prophase oocytes. On contacting the oocyte, the pregranulosa cells become cuboidal in shape, wrap the diplotene stage oocyte as a discontinuous layer and increase the content of cytoplasmic organelles and inclusions. The oocytes increase in size and are arrested in diplotene when the granulosa cells become flat and form a continuous layer. Soon a perivitelline space appears between the oolemma and granulosa cells, completing the process of assembly of follicles. Thus, the events in the establishment of follicles in the caecilian ovary are described.

The specific activities of three lipogenic enzymes, malic enzyme (ME), glucose-6-phosphate dehydrogenase (G6PDH) and isocitrate dehydrogenase (ICDH), in liver and heart and two transaminases (AST & ALT) in liver and muscle, were studied in response to the in vivo and in vitro administration of growth hormone (GH) in a teleost Anabas testudineus. Ovine growth hormone (oGH) in vivo significantly reduced the activities of lipogenic enzymes, except for heart G6PDH, which showed an increase at the highest dose of hormone. Transaminase activity either increased or decreased depending on the dose of GH. The lowest dose of hormone employed (0.1 microg/gm b/w) exhibited a stimulatory effect and the highest dose (0.5 microg/gm. b/w) an inhibitory effect on transaminase activity. Both ovine GH and carp GH (oGH and cGH) in vitro significantly reduced the activities of ME, G6PDH and ICDH. Activities of AST and ALT were increased by oGH and cGH in vitro. The present study reveals that irrespective of origin, GH in vitro has a direct inhibitory effect on lipogenic enzymes ME, G6PDH, ICDH and a stimulatory effect on transaminases AST and ALT in A. testudineus, thus favoring gluconeogenesis.