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L I Lowney

Publications and source records attributed to L I Lowney.

10 recordsLinked to original sources
PubMed1988

6-Acetylmorphine: a natural product present in mammalian brain.

Recently, we described three substances in bovine hypothalamus, adrenal, and rat brain recognized by antisera raised against morphine, and we identified one as morphine and another as codeine by GC/MS. We now report the identification of the third immunoreactive (ir) morphinan from bovine brain as 6-acetylmorphine by chemical conversion to morphine, GC/MS, and high-resolution mass measurement. 6-Acetylmorphine has not previously been described as a natural product in plants or animals, but it has long been known as the metabolite in part responsible for the biological properties of heroin. However, we have excluded slaughter-house or laboratory contamination by any morphinan as well as derivation from the morphine in tissues during our procedures. 6-Acetylmorphine is known to be more potent than morphine in vivo chiefly by virtue of its greater penetration into the central nervous system. Should morphinans prove to have physiological functions in animals, the properties of 6-acetylmorphine make it ideal for fulfilling the role of a peripheral-to-central hormone.

Animals↗
PubMed1986

Morphine and codeine from mammalian brain.

Recently, we described the presence of six immunoreactive (ir) morphinans in bovine adrenal and hypothalamus and identified one as morphine [Goldstein, A., Barrett, R. W., James, I. F., Lowney, L. I., Weitz, C. J., Knipmeyer, L. L. & Rapaport, H. (1985) Proc. Natl. Acad. Sci. USA 82, 5203-5207]. We now report that ir morphinans corresponding to the previously reported peak 1 (morphine), peak 4, and peak 5 are consistently present in extracts of bovine hypothalamus and variably present in extracts of bovine adrenal and rat brain. We no longer detect the previously reported peaks 2, 3, or 6, and we have established that they were contamination artifacts. Peak 1 is coeluted with morphine in two distinct reversed-phase HPLC systems, as is peak 4 with codeine. We have purified peak 1 and peak 4 compounds from bovine hypothalamus and determined their identities by gas chromatography/mass spectrometry (GC/MS): peak 1 is confirmed to be morphine and peak 4 is codeine.

Adrenal Glands↗
PubMed1985

Morphine and other opiates from beef brain and adrenal.

We describe nonpeptide opioids found in extracts of beef hypothalamus and adrenal, which are recognized by antisera raised against morphine. Four have been purified to homogeneity. One is morphine. The structures of the other three have not been determined yet. None of them are derived from morphine or normorphine after extraction from the tissues. It is not known whether the opiates described here are of endogenous or exogenous origin.

Adrenal Glands↗
PubMed1981

Porcine pituitary dynorphin: complete amino acid sequence of the biologically active heptadecapeptide.

The full primary structure of the very potent opioid peptide dynorphin, from porcine pituitary, has been determined. It is (H)Tyr-Gly-Gly-Phe-Leu-Arg-Arg-Ile-Arg-Pro-Lys-Leu-Lys-Trp-Asp-Asn-Gln(OH). The synthetic peptide with this sequence behaves identically to natural dynorphin in a number of ways, and it has the same potency in the guinea pig ileum myenteric plexus--longitudinal muscle bioassay. The potency is accounted for by the first 13 residues.

Amino Acid Sequence↗
PubMed1979

Dynorphin-(1-13), an extraordinarily potent opioid peptide.

We describe the opioid properties of a tridecapeptide, the sequence of which corresponds to the NH2-terminal sequence of dynorphin, a novel porcine pituitary endorphin. It contains [Leu]enkephalin. In the guinea pig ileum longitudinal muscle preparation it is about 700 times more potent than [Leu]enkephalin. Its effects in this tissue are blocked completely by naloxone, but the apparent affinity of naloxone is 1/13th that for blockade of [Leu]enkephalin or normorphine. In the mouse vas deferens, this peptide is 3 times more potent than [Leu]enkephalin. Well-washed rat brain membranes degrade the peptide rapidly, suggesting the presence of a membrane-bound degradative enzyme. The peptide displays considerable immunoreactivity in assays with antisera that have been used for the immunohistochemical localization of [Leu]enkephalin. The remarkable enhancement of the potency of [Leu]enkephalin by the COOH-terminal extension -Arg-Arg-Ile-Arg-Pro-Lys-Leu-Lys-OH suggests new interpretations concerning the structure of opiate receptors and the function of the enkephalin pentapeptides.

Amino Acid Sequence↗
PubMed1974

Partial purification of an opiate receptor from mouse brain.

A proteolipid isolated from a lipid extract of mouse brain demonstrates stereospecific binding properties for levorphanol. It is present only in neuronal tissue and most abundant in the rhombencephalon. One component saturates at a concentration corresponding to maximum pharmacologic effect in vivo. The estimated mass is 60,000 daltons per bound opiate molecule.

Animals↗
PubMed1971

Stereospecific and nonspecific interactions of the morphine congener levorphanol in subcellular fractions of mouse brain.

A METHOD IS DESCRIBED FOR ANALYZING THE ASSOCIATION OF THE OPIATE NARCOTIC LEVORPHANOL WITH BRAIN TISSUE INTO THREE COMPONENTS: nonsaturable, saturable nonspecific, and saturable stereospecific. The method may be of general applicability for the study of the interaction of drugs with body tissues. In mouse brain the stereospecific binding of levorphanol represents only 2% of the total association of drug with tissue, and it was found only in certain membrane fractions. The material responsible for the stereospecific binding might be the opiate receptor.

Animals↗