Perinatal alcohol exposure enhances nocistatin levels in adulthood

Deciphering intracellular localization and physiological role of nociceptin and nocistatin

Nociceptin and nocistatin are endogenous ligands of G protein coupled receptor family. Numerous techniques have been used to study the diverse parameters including, localization, distribution and ultrastructure of these peptides. The majority of the study parameters are based on their physiological roles in different organ systems. The present study presents an overview of the different methods used for the study of nociceptin, nocistatin and their receptors. Nociceptin has been implicated in many physiological functions including, nociception, locomotion, stressed-induced analgesia, learning and memory, neurotransmitter and hormone release, renal function, neuronal differentiation, sexual and reproductive behavior, uterine contraction, feeding, anxiety, gastrointestinal motility, cardiovascular function, micturition, cough, hypoxic-ischemic brain injury, diuresis and sodium balance, temperature regulation, vestibular function, and mucosal transport. It has been noted that the use of light and electron microscopy was less frequent, though it may be one of the most promising tools to study the intracellular localization of these neuropeptides. In addition, more studies on the level of circulating nociceptin and nocistatin are also necessary for investigating their clinical roles in health and disease. A variety of modern tools including physiological, light and electron microscopy (EM) are needed to decipher the extent of intracellular localization, tissue distribution and function of these peptides. The intracellular localization of nociceptin and nocistatin will require a high resolution transmission EM capable of identifying these peptides and other supporting molecules that co-localize with them. A tracing technique could also elucidate a possible migratory ability of nociceptin and nocistatin from one cellular compartment to the other.

The biological basis and clinical significance of hormonal imprinting, an epigenetic process

The biological phenomenon, hormonal imprinting, was named and defined by us (Biol Rev, 1980, 55, 47-63) 30 years ago, after many experimental works and observations. Later, similar phenomena were also named to epigenetic imprinting or metabolic imprinting. In the case of hormonal imprinting, the first encounter between a hormone and its developing target cell receptor-usually at the perinatal period-determines the normal receptor-hormone connection for life. However, in this period, molecules similar to the target hormone (members of the same hormone family, synthetic drugs, environmental pollutants, etc), which are also able to bind to the receptor, provoke faulty imprinting also with lifelong-receptorial, behavioral, etc.,-consequences. Faulty hormonal imprinting could also be provoked later in life in continuously dividing cells and in the brain. Faulty hormonal imprinting is a disturbance of gene methylation pattern, which is epigenenetically inherited to the further generations (transgenerational imprinting). The absence of the normal or the presence of false hormonal imprinting predispose to or manifested in different diseases (e.g., malignant tumors, metabolic syndrome) long after the time of imprinting or in the progenies.

Effect of perinatal stress on the biogenic amine neurotransmitter level of the adult rat's brain

The amount of biogenic amines (dopamine and serotonin) and their metabolites (DOPAC, HVA, 5-HIAA, and 5-HTOL) in five regions of the brain (frontal cortex, hypothalamus, hippocampus, striatum, and brainstem) was studied in the male and female offspring of control and perinatally (48 h before birth or 48 h after birth) food and water deprived dams, when they were three months old, by using HPLC-EC determination. The increase of amine or metabolite level was dominant (19 values increased and 10 decreased related to control). Before-birth stress caused increase in 9 case and only 2 decreased, while in the case of after-birth stress 10 increased and 8 decreased. However, though there is no possibility to decide an exact tendency of direction, the after-birth stress (transmitted by milk) has more expressed effect. Striatum and brainstem were the most touched regions. There was a gender dependence with the dominance of males, except striatum. Blood plasma nociceptin level was also studied and there was a significant elevation in males after pre- and postnatal deprivation, while in females only after postnatal deprivation. The importance of the results in correlation with other stress effects is discussed.