Antitumor immunity transfer by a factor isolated from lymphocytes of tumor bearer

Low-molecular extracts (LMEs) of lymphocytes were obtained from spleen of noninbred rats using our experimental model of intraorganic growth of Guerin's carcinoma. They were intended to transfer immune reaction to tumor antigens in vitro. It was LMEs developed prior to tumor progression in spleen that showed immunospecific activity with respect to tumor cells. Also, they had marked antigen-independent immunopharmacological activity. Single intravenous injection of LMEs100 pg given on day 7 of tumor growth stimulated antitumor resistance in intact rats within a short time. It prevented tumor cells engrafting in 60% of tumors. A tumor-specific factor has been evolved capable of immune reaction transfer to tumor antigens in vitro thus preventing tumorigenesis in recipients in vivo.     

Colocalization of vasopressin and oxytocin in hypothalamic magnocellular neurons in water-deprived rats

The posterior lobe hormones vasopressin and oxytocin are expressed in mutually-exclusive sets of magnocellular hypothamalic neurons. However, under certain functional conditions a partial coexpression has been observed. In the present study we subjected adult rats to long-term osmotic stress by water deprivation for up to 3 days.After 3 days, a marked reduction of vasopressin immunostaining was observed in the paraventricular and supraoptic nuclei as compared with controls. Coexistence of oxytocin and vasopressin occurred in a portion of the magnocellular neurons. Many fibers of the hypothalamic-neurohypophyseal tract contained both peptides. Rehydration for 24 h after 3 days of thirsting resulted in a light recovery of vasopressin immunoreactivity with almost none magnocellular neurons containing both nonapeptides. Our findings indicate that magnocellular hypothalamo neurohypophysial neurons are capable of oxytocin and vasopressin coexpression upon extended osmotic stress.     

Oxytocin Facilitates Pavlovian Fear Learning in Males

In human evolution, social group living and Pavlovian fear conditioning have evolved as adaptive mechanisms promoting survival and reproductive success. The evolutionarily conserved hypothalamic peptide oxytocin is a key modulator of human sociality, but its effects on fear conditioning are still elusive. In the present randomized controlled study involving 97 healthy male subjects, we therefore employed functional magnetic resonance imaging and simultaneous skin conductance response (SCR) measures to characterize the modulatory influence of intranasal oxytocin (24 IU) on Pavlovian fear conditioning. We found that the peptide strengthened conditioning on both the behavioral and neural levels. Specifically, subjects exhibited faster task-related responses and enhanced SCRs to fear-associated stimuli in the late phase of conditioning, which was paralleled by heightened activity in cingulate cortex subregions in the absence of changes in amygdala function. This speaks against amygdalocentric views of oxytocin having pure anxiolytic-like effects. Instead, it suggests that the peptide enables extremely rapid and flexible adaptation to fear signals in social contexts, which may confer clear evolutionary advantages but could also elevate vulnerability for the pathological sequelae of interpersonal trauma.     

Homer 1 - a new player linking the hypothalamic-pituitary-adrenal axis activity to depression and anxiety

Homer 1 gene products are involved in the regulation of synaptic transmission and plasticity. Beside other deficits, the Homer 1 knockout (KO) mice show distinct behavioural abnormalities, such as anxiety and depression-like behaviours. In addition, we recently reported that the global deletion of the Homer 1 proteins in mice leads to a?conspicuous endocrine phenotype linked to hypertrophy of the adrenal cortex, elevated basal and/or adrenocorticotropic hormone-induced corticosterone and aldosterone release in vitro and in vivo, as well as a?drastic increase in the adrenocorticotropic hormone receptor mRNA in the adrenocortical cells. Interestingly, the basal secretion of adrenocorticotropic hormone was not changed in these mutants, which is in line with our recent observations, suggesting that the central limb of the hypothalamic-pituitary-adrenal axis (namely hypothalamic corticotropin-releasing hormone levels and the activation of its neurons in response to restraint stress) is not affected in the Homer 1 KO mice. On the contrary, the elevation of both plasma and intra-adrenal corticosterone and aldosterone concentrations in these mutants clearly indicates that the alteration primarily occurred in the adrenal cortex. We propose that excessive steroid release may contribute to depression- and anxiety-like behaviours and that the Homer 1 gene products may be involved in the pathogenesis of these stress-related mood disorders. Keywords: Homer 1, HPA axis, CRH, ACTH, adrenal cortex, corticosterone, aldosterone.