The pineal hormone Melatonin plays an important role in the regulation of the circadian sleep/wake cycle, mood, and perhaps immune functions, carcinogensis and reproduction. The human circadian rhythm of melatonin release from the pineal gland is tightly synchronized with the habitual hours of sleep. Peri- and postmenopausal women often complain of difficulties initiating and/or maintaining sle...

The neuroendocrine and immune systems help an organism cope with changing environmental conditions. In recent years, melatonin, a neural hormone synthesized and secreted primarily by the pineal gland (Pelham et al., 1972; Pang and Ralph, 1975), has been suggested to have immunomodulatory roles. The involvement of melatonin in the establishment of a pineal-immune system regulatory axis is curren...

Melatonin, synthesized in and released from the pineal gland, has been demonstrated by multiple in vivo and in vitro studies to have an oncostatic role in hormone-dependent tumors. Furthermore, several clinical trials point to melatonin as a promising adjuvant molecule to be considered for cancer treatment. In the past few years, evidence of a broader spectrum of action of melatonin as an antit...

Nocturnal synthesis of melatonin in the pineal gland is controlled by a circadian rhythm in arylalkylamine N-acetyltransferase (AANAT) enzyme activity. In the rodent, Aanat gene expression displays a marked circadian rhythm; release of norepinephrine in the gland at night causes a cAMP-based induction of Aanat transcription. However, additional transcriptional control mechanisms exist. Homeobox...

In this immunohistochemical study we investigate the presence of vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY) during embryonic development in the sheep pineal gland. We use ten ovine embryos at different stages of development (117 to 150 days of prenatal development). The VIP positive fibers were observed along the blood vessels, entering the pineal gland through the pineal caps...

Melatonin (5-methoxy-N-acetyltryptamine), a derivative of the essential amino acid tryptophan, is an indolamine hormone secreted throughout the day. This hormonal molecule is produced mainly in the pineal gland although various other tissues including the gastrointestinal tract are sites of production. Melatonin is an agent that promotes sleep produced mainly at night. It is secreted in the ret...

Several functional and morphological studies have been conducted on the pineal gland in many mammalian species; however, no published reports are available on the role of pineal gland on the gonadal development before and after eyelids separation in puppies. Therefore, this study aimed to trace the postnatal histo-morphological changes in the pineal gland and gonads of puppies before (2, 10 and...

The relationship between the pineal gland and aging has been assumed already nearly a century ago. Recently, melatonin was considered by some authors as a "wonder drug." The present paper tries to summarize the relationship between melatonin and aging in three points. 1. Decline of melatonin production during aging. 2. The role of the pineal gland in the regulation of the ovarian cycle in aged ...

H UMAN pineal gland calcification, which was reported in autopsy specimens about 300 years ago, was first described in the plain skull roentgenogram in 1918 by Sch#{252}ller,’6 who remarked that the gland “very often shows a calcium deposit from the third decade and occasionally even in children.” Subsequent workers confirmed Sch#{252}ller’s observation and established the influence of age on t...

I. Introduction UNTIL 35 yr ago, most scientists did not take research on the pineal gland seriously. The decade beginning in 1956, however, provided several discoveries that laid the foundation for what has become a very active area of investigation. These important early observations included the findings that, 1), the physiological activity of the pineal is influenced by the photoperiodic en...