Caffeine and Nutrition: an Overview - Caffeine: Chemistry, Analysis, Function and Effects - page 14

processes of subcortical nuclei involved in the LI phenomenon, in comparison
to the cortical processes underlying CSD. This suggestion receives support
from our own data documenting a lack of action of dopaminergic drugs on
CSD in the rat brain (see the final part of the discussion in Aguiar et al., 2011).
The suggestion of a dopamine-based modulation of caffeine at the subcortical
but not at the cortical level deserves further investigation.
Finally, we must comment on the complex task of extrapolating
experimental data from rats to humans. This task has obvious limitations
and requires considerable caution. Despite such pitfalls, the main overall
conclusion from the converging pieces of evidence presented here is that the
development of experimental models devoted to investigating this theme is
highly desirable and is surely valid in the case of behavioral and
electrophysiological models. In this context, we are convinced that the LI
and CSD models are valuable for understanding the relationship among
caffeine consumption, nutrition, and development and function of the
organism. The analysis of LI and CSD features under conditions varying
from moderate-eventual to intense-habitual caffeine intake, as well as under
nutritional deficiency, constitutes an interesting experimental approach for
investigating the neurophysiological effects of nutritional and non-nutritional
conditions. An understanding of the mechanisms by which such conditions
affect the phenomena of LI and-or CSD may be useful in the development of
more effective treatment strategies for diseases presumably associated with
those phenomena, such as attention-disturbance-related diseases in the case of
LI and epilepsy and migraine in the case of CSD.

d n 0 t 2 n g | 3

Summary Points

N

The daily consumption of caffeine can produce positive or negative impact
on physiologic processes in normal human beings, and this constitutes a
worldwide medical- and public health matter of concern.

N

In the present chapter, data from experiments in the rat on the effect of
caffeine on one behavioral and one electrophysiological phenomenon,

designated respectively as latent inhibition [LI] and cortical spreading

depression [CSD], have been discussed.
N Considering that malnutrition early in life can disrupt the organization of
the developing organism, we investigated and discussed the interaction
between caffeine and nutritional deficiency on the LI and CSD phenomena.
N The administration of caffeine during LI conditioning impaired selective
attention in rats in a dose-dependent way, with the dose of 30 mg kg -1
caffeine being effective, but not the treatment with 15 mg kg -1 .
N Caffeine antagonized LI in both well-nourished and early-malnourished
rats, respectively fed a commercial chow diet with 22% protein and a
qualitatively and quantitatively protein-deficient diet (with 8% protein

mostly of vegetable sources).