The effect of harmaline on seizures induced by amygdala kindling in rats

ABSTRACT

Objective: Harmaline and other beta-carbolines act as an inverse agonist for GABA-A receptors and cause central nervous system stimulation and anxiety; thus, it may act hypothetically as a potential seizure augmenter. To examine the hypothesis, the effect of harmaline during the seizures induced by amygdala kindling is investigated here.

Methods: Seven groups of male rats were kindled by daily electrical stimulation of the amygdala. After being kindled, Groups I–III, respectively, received 5, 15 and 50 mg/kg harmaline through intraperitoneal injection. The rats in Groups IV and V received vehicle daily (1 ml/kg) and harmaline (5 mg/kg) daily through intraperitoneal injection. Groups VI and VII received artificial cerebrospinal fluid and harmaline (50 mM) through intraventricular injection, respectively.

Results: In addition to significant increase of some seizure parameters in the fully kindled groups, harmaline significantly increased cumulative afterdischarge duration (P < 0.05) and decreased stage 1 latency (P < 0.01) in the acquisition groups (Groups V and VII). In Group VII, seizure duration showed a significant increase (P < 0.01) while stage 1 latency and stage 4 latency decreased significantly (P < 0.01).

Discussion: According to the results, it is suggested that harmaline may increase neuronal activity and the production of high-frequency action potentials by stimulating NMDA receptors and inhibiting GABA receptors. Overall, drugs and plants containing harmaline may be harmful to epileptic-susceptible people during some traditionally and costume treatments, so these should be avoided.

KEYWORDS:

• Seizures
• harmaline
• kindling
• amygdala

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by Grant No. 3.25636 (December/12/2012) from Ferdowsi University of Mashhad, Mashhad, Iran and Grant No. 93088 from Research Affairs of Sabzevar University of Medical Sciences, Sabzevar, Iran.

Notes on contributors

Azam Alenajaf

Azam Alenajaf is graduated in Animal Physiology from Ferdowsi University of Mashhad. She holds a bachelor of biology and a diploma in experimental sciences. Now he is the teacher of biology. He was interested in studying the environmental factors on epilepsy.

Ehsan Mohebi

Ehsan Mohebi is graduated in Laboratory Sciences. He has publications in epilepsy, Alzheimer's, diabetes, medicine and sports. He also was interested in studying the environmental factors on epilepsy.

Ali Moghimi

Ali Moghimi holding a PhD in physiology (Neurophysiology). He has more than 60 research articles published in ISI and national qualified journals in the field of neurobehavioral and experimental epilepsy and also several posters and lectures presented in national and international conferences. Dr. Moghimi is working as academic staff at Ferdowsi University of Mashhad, Faculty of science, Dept. of Biology from 1997. His lectures are Neuroanatomy, Neurophysiology of Behavior and electrophysiology (for MsC and PhD students of Physiology), Physiological Psychology, Neuropsychology and General physiology (for psychology students) and also Medical physiology for Med students.

Masoud Fereidoni

Masoud Fereidoni has focused on nervous system function specially in the field of pain during his PhD when he did his PhD at Tarbiat Modares University of Tehran, Iran. Afterward, he became a professor of neuroscience and a research group leader as head of Behavior, neuro-degenerative/inflammation laboratory at the department of biology, Faculty of Science, Ferdowsi University of Mashhad, Iran. Research in his group is more concentrated in neuroinflammation and neurodegeneration using some cognitive and behavioral, cellular and molecular examinations both in vivo and in vitro, thereby connect his experience in the fields of neurobiology to the areas of neurodegenerative disease.

Mohammad Mohammad-Zadeh

Mohammad Mohammad-Zadeh has focused on nervous system function specially in the field of Kindling and Field potential recording during his PhD when he did his PhD at Tarbiat Modares University of Tehran, Iran. Now he is Associated professor of Physiology and have a laboratory at the department of Physiology, Faculty of Medicine, Sabzevar University of Medical Sciences, Iran. Research in his Lab. is more concentrated in epilepsy field using some behavioral, electrophysiological, cellular and molecular examinations.