Caffeine consumption disrupts hippocampal long-term potentiation in freely behaving rats

Abstract

Caffeine, one of the most commonly consumed psychoactive substances in the world, has long been known to alter neurological functions, such as alertness, attention, and memory. Despite caffeine's popularity, systematic investigations of its effects on synaptic plasticity in the brain are still lacking. Here we used a freely behaving rodent model of long‐term potentiation (LTP), a frequently studied form of synaptic plasticity, to assess the effects of caffeine consumption on hippocampal plasticity. LTP, which is a persistent increase in the strength of synaptic connections between neurons, is a cellular mechanism widely considered to underlie the processes of learning and memory. A group of 10‐week‐old Sprague–Dawley rats were administered caffeine (1 g/L) in their drinking water 3 weeks prior to collection of electrophysiological data. Another group of age‐matched animals received tap water and served as controls. Stimulating and recording electrodes were chronically implanted in the perforant pathway (PP) and dentate gyrus (DG) region of the hippocampus, respectively, to permit stable electrophysiological recordings of synaptic transmission at this synapse. Population spike amplitude (PSA) measures of LTP induction and duration were acquired in vivo while animals were freely behaving using a well‐established electrophysiological recording protocol. Results indicate caffeine‐treated rats (n = 9) had a significantly (P < 0.05) reduced level of LTP induction compared with controls (n = 10). More studies are needed to identify the exact mechanism through which caffeine alters LTP induction in this freely behaving model of synaptic plasticity.

Caffeine-induced Plasticity of Grey Matter Volume in Healthy Brains: A placebo-controlled multimodal within-subject study

“…At the same time, however, there was lack of a commensurate response in SWA as the due synaptic recovery from the toned-up neuronal strength. A deficient synaptic restoration followed by the continuous administration of caffeine on the next day may presumably maintain the cellular stress, inhibit the functions of hippocampal pyramidal cells [33][34][35] due to exhaustion, and, in the long run, impair memory performance as observed in our study as well as other animal studies on daily administration of caffeine 34 and adenosine antagonists 53 .…”

“…Caffeine interferes with sleep homeostasis by dampening the accumulation of sleep pressure through the antagonism on adenosine A1 and A2A receptors 15,32 . Evidence in animals shows that acute or long-term caffeine consumption inhibits the long-term potentiation (LTP) 33 , neurogenesis 34,35 , and cell proliferation 36 in hippocampus, and can impair learning and memory 34 . However, it is still not clear whether daily caffeine consumption leads to cerebral structural modifications in healthy populations through the constant impact on sleep homeostasis, despite a number of studies exploring the functional neuroprotective effect of caffeine on Parkinson's and Alzheimer's disease 37,38 .…”

Cafeína y comportamiento animal. Análisis sobre condiciones experimentales

“…Institute en 1906 para fines de investigación biomédica, y se trata de la primera rata empleada como organismo modelo en estu-la administración de cafeína [31][32][33][34][35][36][37][38][39][40][41][42], donde tradicionalmente la actividad horizontal y vertical se evalúa por el número de crossings por un sistemas de fotocélulas, el número de líneas cruzadas y la latencia. La prueba de evitación pasiva también conocida como prueba de evitación inhibitoria, es otra opción que permite estudiar el efecto de la cafeína sobre el aprendizaje adquirido y la memoria [5,17,29,31,37].…”

“…Cepa empleada [7,9,15,18,19,20,1,24,36,43,45,46,47,48,49,50] Ratas macho Wistar adultas y jóvenes [36] Ratas embarazadas Wistar [22] Ratas hembras Wistar apareadas; ratas macho Wistar [11,12,14,32,37,38] Ratas macho Sprague,Dawley [17] Ratas embarazadas Sprague,Dawley [28] Ratas hembras Sprague,Dawley; Ratas macho para apareamiento [30,31] Ratas macho Long Evans [5] Ratones machos Swiss [13] Ratones machos albinos Swiss CD1; ratones Knockout carentes de receptores A2A y controles de tipo silvestre [37] Ratones macho albinos Swiss OF1 [27,35] Ratones machos albinos (CF1) [29] Ratones macho CF1 [16] se evaluó el efecto de la cafeína en la animales de ambos géneros. Zahniser et al [33] utilizan ratones machos y hembras congénicas N5; da Silva et al [36] experimentan con ratas embarazadas Wistar y machos de la misma cepa; Soellner et al [28] emplean ratas hembras y machos Sprague,Dawley para apareamiento así como Abreu et al [22] que usan ratas macho y hembras Wistar.…”

“…Por su parte Sousa et al [45] afirman que la cafeína provoca alteraciones en el sistema canabinoide en la corteza y el hipocampo, con implicaciones funcionales en la memoria espacial. El estudio de Blaise et al [38] señala que ratas tratadas con cafeína presentan una reducción en la inducción de la potenciación a largo plazo (LTP), significativamente menor en comparación con los controles. Este hallazgo, que revela una disminución en el mecanismo de LTP en ratas tratadas con cafeína, contrasta con un estudio realizado en el 2015 que indicaba que la exposición a la cafeína no alteraba significativamente la LTP [40].…”