Oxytocin in the context of Positive feedback

Orgasm (from Greek ὀργασμός, orgasmos; "excitement, swelling"), sexual climax, or simply climax, is the sudden release of accumulated sexual excitement during the sexual response cycle, characterized by intense sexual pleasure resulting in rhythmic, involuntary muscular contractions in the pelvic region. Orgasms are controlled by the involuntary or autonomic nervous system and are experienced by both males and females; the body's response includes muscular spasms (in multiple areas), a general euphoric sensation, and, frequently, body movements and vocalizations. The period after orgasm (known as the resolution phase) is typically a relaxing experience due to the release of the neurohormones oxytocin and prolactin, as well as endorphins (or "endogenous morphine").

Human orgasms usually result from physical sexual stimulation of the penis in males (typically accompanied by ejaculation) and of the clitoris (and vagina) in females. Sexual stimulation can be by masturbation or with a sexual partner (penetrative sex, non-penetrative sex, or other sexual activity). Physical stimulation is not a requisite, as it is possible to reach orgasm through psychological means. Getting to orgasm may be difficult without a suitable psychological state. During sleep, a sex dream can trigger an orgasm and the release of sexual fluids (nocturnal emission).

Labor induction is the procedure where a medical professional starts the process of labor (giving birth) instead of letting it start on its own. Labor may be induced (started) if the health of the mother or the baby is at risk. Induction of labor can be accomplished with pharmaceutical or non-pharmaceutical methods.

In Western countries, it is estimated that one-quarter of pregnant women have their labor medically induced with drug treatment. Inductions are most often performed either with prostaglandin drug treatment alone, or with a combination of prostaglandin and intravenous oxytocin treatment.

Generosity (also called largesse) is the virtue of being liberal in giving, often as gifts. Generosity is regarded as a virtue by various world religions and philosophies and is often celebrated in cultural and religious ceremonies.

Scientific investigation into generosity has examined the effect of a number of scenarios and games on individuals' generosity, potential links with neurochemicals such as oxytocin, and generosity's relationship with similar feelings such as empathy.

Neuroendocrine cells are cells that receive neuronal input (through neurotransmitters released by nerve cells or neurosecretory cells) and, as a consequence of this input, release messenger molecules (hormones) into the blood. In this way they bring about an integration between the nervous system and the endocrine system, a process known as neuroendocrine integration. An example of a neuroendocrine cell is a cell of the adrenal medulla (innermost part of the adrenal gland), which releases adrenaline to the blood. The adrenal medullary cells are controlled by the sympathetic division of the autonomic nervous system. These cells are modified postganglionic neurons. Autonomic nerve fibers lead directly to them from the central nervous system. The adrenal medullary hormones are kept in vesicles much in the same way neurotransmitters are kept in neuronal vesicles. Hormonal effects can last up to ten times longer than those of neurotransmitters. Sympathetic nerve fiber impulses stimulate the release of adrenal medullary hormones. In this way the sympathetic division of the autonomic nervous system and the medullary secretions function together.

The major center of neuroendocrine integration in the body is found in the hypothalamus and the pituitary gland. Here hypothalamic neurosecretory cells release factors to the blood. Some of these factors (releasing hormones), released at the hypothalamic median eminence, control the secretion of pituitary hormones, while others (the hormones oxytocin and vasopressin) are released directly into the blood.

The κ-opioid receptor or kappa opioid receptor, abbreviated KOR or KOP for its ligand ketazocine, is a G protein-coupled receptor that in humans is encoded by the OPRK1 gene. The KOR is coupled to the G protein G_i/G₀ and is among related receptors that bind opioid-like compounds in the brain and are responsible for mediating the effects of these compounds. These include altering nociception, mood, reward system, and motor control.

KOR is one of the two opioid receptors that bind dynorphin opioid peptides as the primary endogenous ligands, the other being newly deorphanized GPR139 receptor. In addition, oxytocin was found to be a positive allosteric modulator of KOR, and a variety of natural alkaloids, terpenes and synthetic ligands bind to the receptor.

5-HT receptors, 5-hydroxytryptamine receptors, or serotonin receptors, are a group of G protein-coupled receptor and ligand-gated ion channels found in multiple tissues including the central and peripheral nervous systems. They mediate both excitatory and inhibitory neurotransmission. The serotonin (i.e., 5-hydroxytryptamine, hence "5-HT") receptors are activated by the neurotransmitter serotonin, which acts as their natural ligand.

The serotonin receptors modulate the release of many neurotransmitters, including glutamate, GABA, dopamine, epinephrine / norepinephrine, and acetylcholine, as well as many hormones, including oxytocin, prolactin, vasopressin, cortisol, corticotropin, and substance P, among others. Serotonin receptors influence various biological and neurological processes such as aggression, anxiety, appetite, cognition, learning, memory, mood, nausea, sleep, and thermoregulation. They are the target of a variety of pharmaceutical and recreational drugs, including many antidepressants, antipsychotics, anorectics, antiemetics, gastroprokinetic agents, antimigraine agents, psychedelics (hallucinogens), and entactogens.

A social disorder is a type of psychiatric condition that includes social deficits and affects social functioning. Examples of social disorders include social phobia (social anxiety disorder), autism spectrum disorders, schizophreniform disorders like schizophrenia and schizoid personality disorder, and certain other personality disorders.

Oxytocin receptor agonists, like oxytocin and LIT-001, are of theoretical interest in the potential medical treatment of social disorders.

The paraventricular nucleus (PVN) is a nucleus in the hypothalamus, located next to the third ventricle. Many of its neurons project to the posterior pituitary where they secrete oxytocin, and a smaller amount of vasopressin. Other secretions are corticotropin-releasing hormone (CRH) and thyrotropin-releasing hormone (TRH). CRH and TRH are secreted into the hypophyseal portal system, and target effector endocrine cells in the anterior pituitary. Dysfunctions of the PVN can cause hypersomnia in mice. In humans, the dysfunction of the PVN and the other nuclei around it can lead to drowsiness for up to 20 hours per day. The PVN is thought to mediate many diverse functions through different hormones, including osmoregulation, appetite, wakefulness, and the response of the body to stress.

The posterior pituitary (or neurohypophysis) is the posterior lobe of the pituitary gland which is part of the endocrine system. Unlike the anterior pituitary, the posterior pituitary is not glandular, but largely a collection of axonal projections from the hypothalamus that terminate behind the anterior pituitary, and serve as a site for the secretion of neurohypophysial hormones (oxytocin and vasopressin) directly into the blood. The hypothalamic–neurohypophyseal system is composed of the hypothalamus (the paraventricular nucleus and supraoptic nucleus), posterior pituitary, and these axonal projections.

The neurohypophysial hormones form a family of structurally and functionally related peptide hormones. Their representatives in humans are oxytocin and vasopressin. They are named after the location of their release into the blood, the neurohypophysis (another name for the posterior pituitary).

Most of the circulating oxytocin and vasopressin hormones are synthesized in magnocellular neurosecretory cells of the supraoptic nucleus and paraventricular nucleus of the hypothalamus. They are then transported in neurosecretory granules along axons within the hypothalamo-neurohypophysial tract by axoplasmic flow to axon terminals forming the pars nervosa of the posterior pituitary. There, they are stored in Herring bodies and can be released into the circulation on the basis of hormonal and synaptic signals with assistance from pituicytes.