In the heart, endogenous adenosine attenuates the β-adrenergic-elicited increase in contractile performance via activation of adenosine A1 receptors. It has been recently reported that this function of adenosine becomes more pronounced with myocardial maturation. The purpose of the present study was to determine whether mature hearts possess a greater sensitivity than immature hearts to this an...

Orexins A and B are two hypothalamic peptides, involved in the central regulation of feeding, which act through two receptor subtypes, named OX1R and OX2R. OX1R is selective for orexin-A, and OX2R binds both orexins. We have investigated the effects of three subcutaneous injections of 10 nmol/kg body weight of orexins on the secretion and proliferative activity of immature (20-day-old) and rege...

The role of RNA synthesis was investigated in the action of chorionic gonadotropin on ovaries of immature rats. Chorionic gonadotropin accelerates the ovarian incorporation of [3H]uridine in uivo into rapidly labeled nuclear RNA within 10 min after hormone injection. Analysis of the RNA base composition, expressed as base ratio (A + U):(G + C), shows that hormonal stimulation of the rate of [3H...

O xybenzone, an organic UV-B and short-wave UV-A filter, has been available for over 40 years; it is widely used in sunscreens and other consumer products in the United States. The Centers for Disease Control and Prevention has estimated the prevalence of oxybenzone exposure in the general US population to be 96.8%. In the past few years, oxybenzone has received increasing attention as a potent...

Background Royal jelly (RJ) is a complementary diet widely prescribed by traditional medicine specialists for treatment of infertility. The aim of present study was to evaluate the effects of RJ on a set of reproductive parameters in immature female rats. MATERIALS AND METHODS In this experimental study, thirty two immature female rats (30-35 g) were divided into four groups (n=8/group): thre...

The dentate gyrus (DG) is a unique structure of the hippocampus that is distinguished by ongoing neurogenesis throughout the lifetime of an organism. The development of the DG, which begins during late gestation and continues during the postnatal period, comprises the structural formation of the DG as well as the establishment of the adult neurogenic niche in the subgranular zone (SGZ). We inve...

Damaged articular cartilage rarely heals or regenerates in middle-aged and elderly adults, suggesting that the chondrogenic potential of mesenchymal stem cells declines with age. To test this hypothesis, we measured the responses of rat bone marrow-derived mesenchymal stem cells (BMSCs) to chondrogenic induction in vitro. BMSCs from immature rats (1 week old), young adult rats (12 weeks old), a...

Cooperative actions of FSH and androgens on initiation, maintenance, and restoration of spermatogenesis have been described. In the present experiments the regulatory effects of FSH on androgen receptor (AR) gene expression in Sertoli cells were studied. In immature rats injection of FSH (1 microgram/g BW, ip) resulted in a rapid down-regulation of testicular AR mRNA expression (4 h), followed ...

Cyclosporin A (CsA) has been shown to be neuroprotective in mature animal models of traumatic brain injury (TBI), but its effects on immature animal models of TBI are unknown. In mature animal models, CsA inhibits the opening of the mitochondrial permeability transition pore (MPTP), thereby maintaining mitochondrial homeostasis following injury by inhibiting calcium influx and preserving mitoch...