The excitability and rhythm of medullary respiratory neurons in the cat are altered by the serotonin receptor agonist 5-methoxy-N,N, dimethyltryptamine.
Brain Research June 13, 1994 DOI: 10.1016/0006-8993(94)91909-7 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study Peer reviewed |
|---|---|
| Population | Cats |
| Interventions | 5-MeODMT cinanserin |
| Dose | 43 ± 8.9 micrograms/kg i.v. (higher), 27 ± 2.78 micrograms/kg i.v. (lower) |
| Topics | 5-MeO-DMT DMT Serotonin |
| Citations | 37 |
| Key findings | 5-MeO-DMT has dose-dependent, opposing effects on medullary respiratory neurons: larger doses suppress firing via presynaptic and postsynaptic 5HT-1A receptor activation, while smaller doses increase neuronal discharge and alter respiratory timing. |
Abstract
5-Methoxy-N,N-dimethyltryptamine (5-MeODMT) is an indolealkylamine which has agonist activity at 5HT receptors. In the present investigation, 5-MeODMT had two types of effects on medullary respiratory neurons of the cat. Iontophoretic administration or i.v. doses (43 +/- 8.9 micrograms/kg) of 5-MeODMT hyperpolarized respiratory neurons and severely reduced action potential discharges. Cinanserin, a 5HT-2/1 c receptor antagonist, when injected i.v. reduced the inhibition produced by i.v. injection of 5-MeODMT. Iontophoresis of cinanserin did not antagonize inhibition produced by iontophoresis of 5-MeODMT or 5-HT. The depression of respiratory discharge by i.v. injection of 5-MeODMT is attributed to presynaptic effects (network depression) and post-synaptic activation of 5HT-1A receptors on respiratory neurons. 5-MeODMT (27 +/- 2.78 micrograms/kg i.v.) also increased discharge frequency of inspiratory and expiratory neurons. Inspiratory neuron discharges were briefer and expiratory neuron discharges occurred earlier in relation to phrenic nerve activity. It is suggested that the effects of the smaller doses are due to binding of 5-MeODMT to 5HT-1A receptors on early inspiratory neurons of the medulla.
Comparable studies
Other experimental studies on 5-MeO-DMT, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Short term changes in the proteome of human cerebral organoids induced by 5-MeO-DMT. Human cerebral organoids | 2017 | Experimental study | |
| Bufo alvarius: a potent hallucinogen of animal origin. Bufo alvarius toad venom | 1994 | Experimental study | |
| Prospective examination of synthetic 5-methoxy-N,N-dimethyltryptamine inhalation: effects on salivary IL-6, cortisol levels, affect, and non-judgment Volunteers | 2019 | Within-subjects experimental study | n = 11 |
| Unmasking of a neonatal somatovesical reflex in adult cats by the serotonin autoreceptor agonist 5-methoxy-N,N-dimethyltryptamine. Adult cats | 1990 | Experimental study | n = 10 |
| Studies on the Mechanism of Action of Monoamine Oxidase: Metabolism of N,N-Dimethyltryptamine and N,N-Dimethyltryptamine-N-Oxide | 1962 | Experimental study |
Citations in the library
Cites 3
- Unmasking of a neonatal somatovesical reflex in adult cats by the serotonin autoreceptor agonist 5-methoxy-N,N-dimethyltryptamine. Brain research. Developmental brain research June 1, 1990
- Intracellular studies on the effects of systemic administration of serotonin agonists on rat facial motoneurons. European Journal of Pharmacology February 26, 1982
- Inhibition of phrenic and sympathetic vasomotor neurons in cats by the serotonin analog 5-methoxy-N,N-dimethyltryptamine. Journal of Pharmacology and Experimental Therapeutics March 1, 1982