A [14C]2-deoxyglucose analysis of the functional neural pathways of the limbic forebrain in the rat. IV. A pathway from the prefrontal cortical-medial thalamic system to the hypothalamus

Changes in direct current (DC) potentials and infra‐slow EEG oscillations at the onset of the luteinizing hormone (LH) pulse

“…Rather, such a link could serve a more general function, tuning activity between the endocrine and central nervous systems. On the basis of the present data it may be speculated that neocortical excitability is down‐regulated in temporal proximity to LH pulse onset, thus coinciding with the inhibitory effect of neocortical stimulation on LH secretion (Caceres & Taleisnik, 1980; Brutus et al . 1984).…”

“…The latter studies imply that changes in neocortical electrical activity in association with pituitary LH secretion result from a direct or indirect collateral hypothalamic output to cortical structures. Although the temporal resolution of the present data do not allow exclusion of an inverse relationship, evidence that stimulation of LHRH/LH secretory activity could be a consequence of changes in activity at the cortical level is scarce (Caceres & Taleisnik, 1980; Brutus et al . 1984).…”

“…An intriguing candidate mediating hypothalmic in¯uences on cortical excitability, DC potentials and infra-slow EEG activity is neuropeptide Y (NPY). Abundant NPY binding sites have been found in human frontal cortex (Statnick et al, 1997;Caberlotto et al, 1998), and NPY release precedes LHRH by » 5 min (Woller et al, 1992). NPY has been shown to produce shifts in EEG frequencies and amplitude, particularly over the frontal cortex, and to in¯uence cortical excitability in vitro as well as after intracerebroventricular administration in rats (Zini et al, 1984;Ehlers et al, 1997;Klapstein & Colmers, 1997;Woldbye et al, 1997).…”

“…1997). Stimulation of the hypothalamus has been found to affect, for instance, cortical slow potential activity and sleep‐related thalamo–cortical spindle activity (Aladjalova, 1964; Rowland, 1968; Suntsova & Burikov, 1997), and electrical stimulation of the frontal neocortex can exert an effect, albeit inhibitory, on luteinizing hormone (LH) secretion (Caceres & Taleisnik, 1980; Brutus et al . 1984).…”

“…Many neuroanatomic pathways relay a direct or indirect interaction between hypothalamus and neocortex (Morecraft et al, 1992;Risold et al, 1997). Stimulation of the hypothalamus has been found to affect, for instance, cortical slow potential activity and sleep-related thalamo± cortical spindle activity (Aladjalova, 1964;Rowland, 1968;Suntsova & Burikov, 1997), and electrical stimulation of the frontal neocortex can exert an effect, albeit inhibitory, on luteinizing hormone (LH) secretion (Caceres & Taleisnik, 1980;Brutus et al, 1984). The objective of the present study was to demonstrate a temporal link between hypothalamus-dependent endocrine activity and neocortical activity in humans.…”