Photoperiod, or length of day, has a predictable annual cycle, making it an important cue for the timing of seasonal behavior and development in many organisms. Photoperiod is widely used among temperate and polar animals to regulate the timing of sexual maturation. The proper sensing and interpretation of photoperiod can be tightly tied to an organism's overall fitness. In photoperiodic mammal...

*Corresponding author: Javad Baharara, Professor, Dept. of Biology & Research Center for Animal Development Applied Biology, Mashhad Branch, Islamic Azad University, Mashhad, Iran, Tel: + 98 5l1 8437092, Fax: + 98 511 8437092, Email: [email protected] Introduction Nowadays, the widespread use of various electrical and telecommunication appliances that produce electromagnetic fields is increasi...

We investigated serum folic acid (FA) levels in patients with erectile dysfunction (ED) and/or premature ejaculation (PE). Fasting serum samples were obtained from 42 patients with ED, 36 with PE, 25 ED patients with PE, and 30 healthy men; the mean intravaginal ejaculation latency time (IELT) was measured during a 4 weeks baseline period. Levels of sex hormones (follicle-stimulating hormone, l...

Given demographic evolution of the population in modern societies, one of the most important health care needs is successful aging with less frailty and dependency. During the last 20 years, a multitude of anti-aging practices have appeared worldwide, aiming at retarding or even stopping and reversing the effects of aging on the human body. One of the cornerstones of anti-aging is hormone repla...

Teleost fishes are the 'champions' of sexual plasticity among vertebrates. Several species have two male reproductive morphs with distinct suites of behavioral, somatic, neuronal, endocrinological, and life history traits. Here, we consider recent studies of the social and neural modulation of sexual plasticity for such species with a focus on two neuropeptides, gonadotropin releasing hormone (...

conclusions the inhibition of mini-puberty period in male rats was demonstrated to have an effect on their testicular function to some extent. results serum t and lh levels peaked at two hours after birth, while fsh peaked at hour 0, and bilateral testicular weight peaked at four hours after birth. the rats that underwent ether inhalation five minutes after birth had markedly reduced serum horm...

1 The availability of large numbers of drugs in the 1960s and 1970s resulted in an explosion of psychopharmacological studies of motivated behaviour, including sexual behaviour. The effects of some drugs, particularly those affecting serotonin and dopamine, on patterns of sexual activity in males and females of a number of non-human species were impressive and encouraged the belief, held by man...