GHRP-6
Growth Hormone Releasing Peptide-6, Growth hormone-releasing hexapeptide, His-D-Trp-Ala-Trp-D-Phe-Lys-NH2
Role of intraamygdaloid acylated-ghrelin in spatial learning.
Tóth. Krisztián K; László. Kristóf K; Lénárd. László L
Key Findings
- Acylated‑ghrelin (50 ng) infused into the basolateral amygdala speeds up spatial learning in the Morris water maze.
- The learning improvement is blocked by pretreatment with the ghrelin receptor antagonist d‑Lys3‑GHRP‑6.
- The antagonist alone does not affect learning, indicating the effect is ghrelin‑specific.
Practical Outcomes
- The study confirms that ghrelin can enhance memory via the amygdala, but it was done with direct brain injections in rats, not with oral or systemic doses usable by people. For biohackers, it suggests the ghrelin pathway is a potential target for cognitive enhancement, yet no clear, safe protocol for humans can be drawn from this work yet.
Summary
In rats, injecting a small amount of the hormone acylated‑ghrelin directly into a part of the amygdala made them learn a water‑maze task faster. The learning boost disappeared when a ghrelin‑blocking peptide (d‑Lys3‑GHRP‑6) was given first, showing the effect is specifically due to ghrelin acting in that brain region.
Abstract
According to recently published papers acylated-ghrelin (A-Ghr) modifies memory and learning. The basolateral nucleus of amygdala (ABL) participates in the regulation of memory and learning mechanisms. Previously we verified A-Ghr responsive neurons in the ABL by electrophysiological methods. In male Wistar rats effects of bilateral intraamygdaloid microinfusion of 50 ng, 100 ng A-Ghr, 15 ng Ghr receptor antagonist d-Lys3-GHRP-6 (ANT) or ANT+50 ng A-Ghr [dissolved in 0.15M sterile saline], or vehicle in 0.4 microl volume were investigated in Morris water maze paradigm. 50 ng A-Ghr significantly reduced latency to find the platform located in one of the quadrants of the maze. Effect of 50 ng A-Ghr was blocked by ANT pretreatment. ANT alone had no effect. Our results show that place learning linked memory processes are facilitated by A-Ghr in the rat ABL. It is a specific effect, because it could be eliminated by ANT pretreatment.
Study Information
pubmed
2010
2010-01-15T00:00:00.000Z
10.1016/j.brainresbull.2009.10.003
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