Perineuronal glial system in the cerebral ganglion of active and hibernating Helix aspersa

The electron microscopical changes in the glial lacunar network that surrounds the large neurons of meso- and metacerebrum of land snail cerebral ganglia were considered, in order to get an insight into the functional role of this peculiar structure in invertebrates. Compared with snails during the active period, in the hibernating animals the extension of glial processes was reduced and the glial processes appeared more regular and stacked around neurons. Moreover, they did not form deep, long interdigitations with neuronal infoldings as during the active period. In particular, data on the ultracytochemical detection of alkaline phosphatase and Ca(2+)/Mg(2+)-ATPase enzyme activities, point to a correlation between the extension of the glial system and its function in the regulation of the extracellular environment. In fact, in hibernating snails, lower reactivity was found on the glial membranes, including those of the trophospongium.     

Thyroidal iodine and thyroglobulin in hibernating and active Richardson's ground squirrels Spermophilus richardsoni

Thyroidal iodine, protein and thyroglobulin (TG) were investigated in a hibernator, Spermophilus richardsoni, sampled in the field and from laboratory-held winter colonies. In field animals, thyroidal iodine and protein contents were similar at onset of hibernation and at terminal arousal. Iodine content was increased in laboratory-held animals, a function of alimentary supply, but no differences were observed between hibernators and non-hibernators. Density sucrose gradients showed that approx. 20% of the TG was present as the 12S precursor sub-unit. No variations in the iodine content, nor the iodoamino acid composition of the TG occurred as a function of hibernation.     

Distribution of endocrine cells in the digestive tract of Alligator sinensis during the active and hibernating period

The digestive tract is the largest endocrine organ in the body; the distribution pattern of endocrine cells varies with different pathological and physiological states. The aim of the present study was to investigate the distributed density of 5-hydroxytryptamine (5-HT), gastrin (GAS), somatostatin (SS) and vasoactive intestinal peptide (VIP) immunoreactive (IR) cells in the digestive tract of Alligator sinensis during the active and hibernating period by immunohistochemical (IHC) method. The results indicated that 5-HT-IR cells were distributed throughout the entire digestive tract, which were most predominant in duodenum and jejunum. The density increased significantly in stomach and duodenum during hibernation. GAS-IR cells were limited in small stomach and small intestine. The density decreased significantly in small stomach during hibernation, while increased in duodenum. What's more, most of the endocrine cells in duodenum were generally spindle shaped with long cytoplasmic processes ending in the lumen during hibernation. SS-IR cells were limited in stomach and small stomach. The density increased in stomach while decreased in small stomach during hibernation, meanwhile, fewer IR cells occurred in small intestine. VIP-IR cells occurred in stomach and small stomach. The density decreased in small stomach, while increased in stomach during hibernation. These results indicated that the endocrine cells in different parts of digestive tract varied differently during hibernation, their changes were adaptive response to the hibernation.     

Amino acid content in several brain regions of the active and hibernating frog, Rana esculenta

1. Total free amino acid contents in the optic lobe and diencephalon increased significantly during hibernation. 2. Free glutamate + glutamine showed significant increases in the cerebral hemisphere, optic lobe, medulla oblongata and diencephalon. 3. Free aspartate + asparagine showed significant increases in the cerebral hemisphere, optic lobe, diencephalon and olfactory lobe. 4. GABA showed a significant change only in the medulla oblongata. 5. Total protein amino acid level in the cerebellum and olfactory lobe decreased significantly during hibernation and most of the amino acids decreased significantly in these regions. 6. The amino acid metabolism during amphibian hibernation differs from that of the mammal.     

Adrenergic receptor density in brown adipose tissue of active and hibernating hamsters and ground squirrels

The ligand-binding characteristics (B(max) and K(D)) of alpha(1)- and beta(1)/beta(2)-adrenoceptors were investigated in membranes prepared from brown adipose tissue (BAT) of warm-acclimated, cold-acclimated, hibernating and arousing ground squirrels (Spermophillus undulatus) and hamsters (Mesocricetus auratus) by specific binding of [(3)H]prazosin and [(3)H]CGP-12177, respectively. The physiological state did not change the affinity for the adrenoceptors in the BAT of ground squirrels and hamsters. There was a significant decrease in alpha(1)-receptor density in arousing ground squirrels and a significant decrease in beta(1)/beta(2) density in hibernating ground squirrels. The level of alpha(1)-receptors was in all conditions higher than that of beta(1)/beta(2) receptors. The results indicate a possible change in balance of adrenoceptor density in the processes of cold acclimation, hibernation and arousal. The balance between the various adrenoceptor subtypes may be important for the final effect of catecholamines in BAT in different physiological states.     

Relationship between body and testis temperatures in the European hedgehog, Erinaceus europaeus, during hibernation and sexual reactivation

Simultaneous telemetry of the body and testis temperatures of 8 hedgehogs was carried out during hibernation and during sexual reactivation in spring. Between October and January, when the testes were involuted, the body/testis temperature differential was variable, with mean daily testis temperatures up to 1 degrees C warmer than body temperatures. From mid-February onwards, when plasma testosterone approached maximal concentrations, mean testicular temperatures stabilized 1.4 +/- 0.2 degrees C below body temperatures. During spermatogenesis testicular temperature of hedgehogs was significantly lower than body temperature. Over the euthermic body temperature range of 34.7-36.2 degrees C, testicular temperatures varied from 34.0 to 34.9 degrees C. Only at body temperatures over 36.2 degrees C did testicular temperature reach 35 degrees C. During spermatogenesis hedgehog testis temperatures are similar to those of many scrotal mammals.     

Isolation and characterization of ATP-dependent proteolytically active ubiquitin in cock testis

1. We have successfully isolated and purified ubiquitin from cock testis by using an inhibitor, p-CMB (p-chloromercuribenzoate), which is one of the inhibitors specific for thiol-proteases and with the following procedures: heating up to 85 degrees C, ammonium sulfate fractionation, gel filtration on Sephadex G-75, chromatography on DE-52 and CM-11 and lyophilization. 2. Amino-acid analysis showed that Ub isolated from cock testis has 76 residues including 6 glycines. 3. Hydrazinolysis and carboxypeptidase digestion were also performed: the C-terminal residue is glycine. 4. The purity was checked by analytical SDS-PAGE and the isolated Ub exhibited only one band. 5. The Ub-dependent proteolysis experiment showed that this Ub was ATP-dependently proteolytically active. 6. In this paper we present evidence that a thiol enzyme is present during the purification procedure.