Long-term food restriction down-regulates the density of serotonin transporters in the rat frontal cortex

Biol Psychiatry. 1997 Jun 15;41(12):1174-80. doi: 10.1016/s0006-3223(96)00265-x.


The influence of feeding rats only half the amount of their normal daily intake of a complete rat chow on the affinity and the density of serotonin (5-HT) transporters was measured in membrane preparations of the frontal cortex and the midbrain by a [3H]paroxetine binding assay. In young rats (10 weeks), a significant reduction of about 30% of the Bmax values of [3H]paroxetine binding occurred in the frontal cortex after 1 and 2 weeks of restricted food intake. No starvation-induced decline of the density of 5-HT transporters was seen in the midbrain. When older rats (50 weeks) were subjected to the same 50% reduction of daily food intake for 2 weeks, no such down-regulation of the density of cortical 5-HT transporters was observed. The affinity of the 5-HT transporters, as indicated by the unchanged Kd values of [3H]paroxetine binding, was not affected by semistarvation in both regions and at both ages. The observed decline of [3H]paroxetine binding sites in the frontal cortex of young adult rats is the first demonstration of long-term regulatory phenomena of brain 5-HT transporters triggered by a physiologic stimulus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aging / metabolism
  • Animals
  • Body Weight / drug effects
  • Body Weight / physiology
  • Carrier Proteins / biosynthesis*
  • Down-Regulation / physiology*
  • Frontal Lobe / drug effects
  • Frontal Lobe / metabolism*
  • Male
  • Membrane Glycoproteins / biosynthesis*
  • Membrane Transport Proteins*
  • Membranes / drug effects
  • Membranes / metabolism
  • Mesencephalon / drug effects
  • Mesencephalon / metabolism
  • Nerve Tissue Proteins / biosynthesis*
  • Paroxetine / pharmacokinetics
  • Rats
  • Rats, Wistar
  • Serotonin Plasma Membrane Transport Proteins
  • Serotonin Uptake Inhibitors / pharmacokinetics
  • Starvation / metabolism*


  • Carrier Proteins
  • Membrane Glycoproteins
  • Membrane Transport Proteins
  • Nerve Tissue Proteins
  • Serotonin Plasma Membrane Transport Proteins
  • Serotonin Uptake Inhibitors
  • Slc6a4 protein, rat
  • Paroxetine