Vegetative anatomy and micromorphology of Salvia divinorum (Lamiaceae) from Mexico, combined with chromatographic analysis of salvinorin A.

Salvia divinorum--a species traditionally cultivated in Oaxaca, Mexico--possesses hallucinogenic properties. It is legally recognized as a controlled substance and prohibited in many countries. The proper identification of the plant, both in fresh and dried forms, is an important issue in crime-prevention campaigns. This paper provides a thorough anatomical description of leaves, petioles, and stems of S. divinorum. Detailed investigation of foliar trichomes was performed and illustrated. In addition, chromatographic analyses, including TLC and HPLC, were applied to fresh and dried plant material, together with the standard reference salvinorin A. A comprehensive identification method for S. divinorum based on a thorough anatomical examination is proposed, combined with chemical analysis for proper plant recognition.

Antinociceptive and hypothermic effects of Salvinorin A are abolished in a novel strain of kappa-opioid receptor-1 knockout mice.

Salvia divinorum is a natural occurring hallucinogen that is traditionally used by the Mazatec Indians of central Mexico. The diterpene salvinorin A was identified as an active component of S. divinorum over 20 years ago, but only recently has biochemical screening indicated that a molecular target of salvinorin A in vitro is the kappa-opioid receptor. We have examined whether salvinorin A, the C2-substituted derivative salvinorinyl-2-propionate, and salvinorin B can act as kappa-opioid receptor agonists in vivo. We found that following intracerebroventricular injection over a dose range of 1 to 30 microg of both salvinorin A and salvinorinyl-2-propionate produces antinociception in wild-type mice but not in a novel strain of kappa-opioid receptor knockout mice. Moreover, both salvinorin A and salvinorinyl-2-propionate reduce rectal body temperature, similar to conventional kappa-opioid receptor agonists, in a genotype-dependent manner. In addition, we determined that salvinorin A has high affinity for kappa 1- but not kappa 2-opioid receptors, demonstrating selectivity for this receptor subclass. Finally, treatment over the same dose range with salvinorin B, which is inactive in vitro, produced neither antinociceptive nor hypothermic effects in wild-type mice. These data demonstrate that salvinorin A is the active component of S. divinorum, selective for kappa(1)-opioid receptors, and that salvinorin A and specific structurally related analogs produce behavioral effects that require the kappa-opioid receptor.

Localization of salvinorin A and related compounds in glandular trichomes of the psychoactive sage, Salvia divinorum.

BACKGROUND AND AIMS: Salvia divinorum produces several closely related neoclerodane diterpenes. The most abundant of these, salvinorin A, is responsible for the psychoactive properties of the plant. To determine where these compounds occur in the plant, various organs, tissues and glandular secretions were chemically analysed. A microscopic survey of the S. divinorum plant was performed to examine the various types of trichomes present and to determine their distribution. METHODS: Chemical analyses were performed using thin layer chromatographic and histochemical techniques. Trichomes were examined using conventional light microscopy and scanning electron microscopy. KEY RESULTS: It was found that neoclerodane diterpenes are secreted as components of a resin that accumulates in peltate glandular trichomes, specifically in the subcuticular space that exists between the trichome head cells and the cuticle that encloses them. Four main types of trichomes were observed: peltate glandular trichomes, short-stalked capitate glandular trichomes, long-stalked capitate glandular trichomes and non-glandular trichomes. Their morphology and distribution is described. Peltate glandular trichomes were only found on the abaxial surfaces of the leaves, stems, rachises, bracts, pedicles and calyces. This was consistent with chemical analyses, which showed the presence of neoclerodane diterpenes in these organs, but not in parts of the plant where peltate glandular trichomes are absent. CONCLUSIONS: Salvinorin A and related compounds are secreted as components of a complex resin that accumulates in the subcuticular space of peltate glandular trichomes.

Salvinorin A, an active component of the hallucinogenic sage salvia divinorum is a highly efficacious kappa-opioid receptor agonist: structural and functional considerations.

The diterpene salvinorin A from Salvia divinorum has recently been reported to be a high-affinity and selective kappa-opioid receptor agonist (Roth et al., 2002). Salvinorin A and selected derivatives were found to be potent and efficacious agonists in several measures of agonist activity using cloned human kappa-opioid receptors expressed in human embryonic kidney-293 cells. Thus, salvinorin A, salvinorinyl-2-propionate, and salvinorinyl-2-heptanoate were found to be either full (salvinorin A) or partial (2-propionate, 2-heptanoate) agonists for inhibition of forskolin-stimulated cAMP production. Additional studies of agonist potency and efficacy of salvinorin A, performed by cotransfecting either the chimeric G proteins Gaq-i5 or the universal G protein Ga16 and quantification of agonist-evoked intracellular calcium mobilization, affirmed that salvinorin A was a potent and effective kappa-opioid agonist. Results from structure-function studies suggested that the nature of the substituent at the 2-position of salvinorin A was critical for kappa-opioid receptor binding and activation. Because issues of receptor reserve complicate estimates of agonist efficacy and potency, we also examined the agonist actions of salvinorin A by measuring potassium conductance through G protein-gated K(+) channels coexpressed in Xenopus oocytes, a system in which receptor reserve is minimal. Salvinorin A was found to be a full agonist, being significantly more efficacious than (trans)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)-cyclohexyl] benzeneacetamide methane-sulfonate hydrate (U50488) or (trans)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)-cyclohexyl] benzeneacetamide methane-sulfonate hydrate (U69593) (two standard kappa-opioid agonists) and similar in efficacy to dynorphin A (the naturally occurring peptide ligand for kappa-opioid receptors). Salvinorin A thus represents the first known naturally occurring non-nitrogenous full agonist at kappa-opioid receptors.