Lysipressin
Also known as: 8-lysine vasopressin, LVP, lysine vasopressin, porcine vasopressin, Diapid, lysine-8-vasopressin
Neurohypophysial nonapeptide hormone; vasopressin analogue
What it is
Lysipressin is the natural antidiuretic hormone found in pigs and many marsupials, used clinically as a nasal spray or injection to reduce excessive urination in conditions like diabetes insipidus. It differs from human vasopressin by a single amino acid and has also been used in diagnostic testing for Cushing's syndrome.
The scientific side
lysipressin (8-lysine vasopressin, LVP) is a nine-amino-acid neurohypophysial peptide that differs from human arginine vasopressin (AVP) only at position 8, where lysine replaces arginine. It acts primarily through vasopressin receptor subtypes. Studies using V2 receptor blockers demonstrated that LVP's antidiuretic actions on epithelial tissues—such as increased transepithelial sodium transport in frog skin—are mediated via V2 receptors, though downstream signalling in some tissues does not appear to be mediated by cAMP, suggesting additional intracellular pathways. In renal tubular cells, V2 receptor activation by LVP promotes water reabsorption and urine concentration, which is the basis for its antidiuretic clinical utility. At V1a receptors, LVP exerts vasopressor effects; one study in decerebrate piglets confirmed that the selective V1a antagonist SR 49059 blocked LVP-induced hypertension at doses of 3 mg/kg intravenously. In porcine myometrium, LVP increased contractility and intracellular calcium concentrations dose-dependently; this effect was inhibited by a selective oxytocin receptor antagonist, indicating that LVP can cross-activate oxytocin receptors in uterine tissue, though oxytocin itself was approximately 57–75 times more potent. In the context of the corticotropic axis, LVP stimulates cortisol secretion via V1 receptors expressed on adrenocortical cells, and this property has been exploited diagnostically to identify aberrant V1 receptor expression in adrenocortical tumours responsible for ACTH-independent Cushing's syndrome. LVP also facilitates its own release within the rat supraoptic nucleus in a receptor-mediated positive feedback loop, a mechanism demonstrated by showing that exogenous LVP increased basal AVP release while a V1/V2 antagonist attenuated osmotically stimulated AVP release. Glycosylation of the lysine side chain at position 8 greatly reduces both antidiuretic and pressor activities and impairs receptor binding, confirming that the free lysine residue at position 8 is critical for full receptor engagement.
Class: Neurohypophysial nonapeptide hormone; vasopressin analogue
Administration & storage
- Administration
- Intramuscular injection (diagnostic test protocols — 10 IU IM)Intravenous bolus and continuous infusion (research settings — clearance studies)Intranasal spray (historical clinical use for diabetes insipidus)
- Storage
- No storage conditions for lysipressin are described in the available abstracts. General peptide hormone storage guidance (refrigeration, protection from light) is standard practice for vasopressin-class hormones but is not sourced from the reviewed abstracts.
Legal & regulatory status
Lysipressin (as Diapid nasal spray) was previously FDA-approved for diabetes insipidus but has been discontinued from the US market; not currently approved or marketed in the US.
Not listed as a prohibited substance on current WADA prohibited lists; no specific mention in publicly available WADA documentation.
No current active approval identified; historically available as Diapid in Canada.
What it's studied for
- Central diabetes insipidus (antidiuretic treatment) Clinical — controlled comparisons and retrospective studies
- Diagnostic stimulus test for Cushing's syndrome (LVP stimulation test) Clinical — prospective diagnostic accuracy study
- Evaluation of adrenocortical tumour V1 receptor expression in ACTH-independent Cushing's syndrome Clinical — retrospective case series with in vitro confirmation
- Antidiuretic hormone in marsupial models of water deprivation (biomarker and physiological research) Preclinical / comparative physiology
- Vasopressor and cardiovascular pharmacology research (V1a receptor studies) Preclinical — in vivo animal pharmacology
- Uterotonic activity and myometrial pharmacology (cross-activation of oxytocin receptors) Preclinical — in vitro porcine tissue
- Renal tubular function and prostaglandin interaction research Clinical — controlled crossover study
- Diabetes insipidus antibody resistance (secondary treatment failure) Clinical — observational cohort
Safety signals
- Antibody formation causing secondary treatment resistance
- Vasopressor / hypertensive effect via V1a receptor activation
- Uterotonic activity via cross-activation of oxytocin receptors in porcine myometrium
- Hyponatremia risk with excessive antidiuretic hormone activity
- Variable sodium control in infants treated with intranasal LVP versus subcutaneous desmopressin
- Osmotic dysregulation and dehydration under extreme conditions (comparative physiology signal)
- ACTH-independent cortisol stimulation in adrenocortical tumours with ectopic V1 receptor expression
- Reduction in renal electrolyte excretion modified by prostaglandin synthesis inhibition
No peer-reviewed studies indexed for this peptide yet.
Frequently asked
How is lysipressin different from desmopressin and human vasopressin?
Lysipressin differs from human arginine vasopressin (AVP) at one amino acid: position 8 carries lysine instead of arginine. Desmopressin (dDAVP) is a synthetic analogue with additional structural modifications that make it highly selective for the V2 (antidiuretic) receptor and much longer-acting. Published studies have shown that patients who develop antibodies to lysipressin or AVP generally retain normal antidiuretic responses to desmopressin, suggesting these antibodies are specific to the natural hormone structures.
Was lysipressin (Diapid) ever an approved medicine?
Yes. Lysipressin was marketed as Diapid nasal spray and used clinically for central diabetes insipidus. Published studies describe its use in infants and children with this condition, and comparative data with subcutaneous desmopressin indicate it was an accepted treatment approach. The product has been discontinued from the US market; current clinical guidelines favour desmopressin.
Why is lysipressin used in Cushing's syndrome testing?
Lysipressin stimulates cortisol secretion via V1 receptors expressed on adrenocortical and pituitary corticotroph cells. Published studies showed that intramuscular LVP (10 IU) can be used diagnostically to distinguish pituitary-dependent Cushing's disease from pituitary-independent forms, and to detect aberrant V1 receptor overexpression in adrenocortical tumours. When combined with overnight dexamethasone pre-treatment, the LVP stimulation test achieved high diagnostic accuracy in a prospective study of 61 subjects.
Can lysipressin cause water retention or low sodium?
Like all antidiuretic hormones acting at V2 receptors, lysipressin promotes water reabsorption in renal tubules, which can lead to water retention and dilutional hyponatremia if doses are excessive or fluid intake is not appropriately restricted. A study of chlorpropamide — which potentiates antidiuretic vasopressin receptor activity — demonstrated that enhanced V2 receptor density was associated with measurable decreases in plasma osmolality. There are no lysipressin-specific hyponatremia case series in the abstracts reviewed; the general vasopressin-class risk applies.
Is lysipressin the same as porcine vasopressin?
Yes. Lysipressin is the natural neurohypophysial vasopressin-like hormone found in pigs (family Suidae) and most macropodid marsupials. Its structural identity (lysine at position 8) was confirmed by amino acid composition and chromatographic studies. It is distinct from the arginine vasopressin found in humans and most other placental mammals.