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A phosphorylated, approximately 110 kDa laminin-binding protein (110 kDa LBP) from mouse brain has been previously identified. This protein recognizes a neurite-outgrowth promoting 19-amino acid synthetic peptide (PA 22-2) derived from the laminin A chain. In the present study, an antibody against the 110 kDa LBP was used to localize immunoreactivity in the normal adult rat brain and also following a stab wound and ischemic lesion. Immunoreactive cells were found in layers II/III and V of the cerebral cortex and within apical dendrites of pyramidal neurons. Specific immunoreactivity was also found in the stratum lucidum in the CA3 region of the hippocampus which exhibited densely stained mossy fibers and terminals. Mechanical and ischemic lesions induced intense immunolabeling of reactive glial cells around the lesion site. The distinct and anatomically restricted localization of the immunostain in adult and lesioned rat brain suggests that 110 kDa LBP-like molecules might have an important function in forebrain structures and may be involved in the response to CNS injury.

In order to survive, all organisms must adapt internally and/ or externally to meet the challenges of the ever-changing environment. The nervous and endocrine systems coordinate and integrate the operation of the other organs of the body to bring about their “homeostatic” adjustments. The Neuroendocrine system is broadly de fined as those structures in the CNS that are concerned with the regulation of endocrine function. Hormones act as regulators of almost all metabolic and functional responses involved in the adaptation of the organism to a complex environment (Prosser, 1958). Thus, the phylogenetic and ontogenetic development of a Neuroendocrine system is indispensable to adaptation since it provides the organism with increasing independence from its physical environment (Mason, 1972; Siegel & Eisenman, 1972).

As an interdisciplinary science, gerontology now includes sociology, psychology, physiology biochemistry and morphology. Biological gerontology is regarded as a relatively young discipline. It has a predominant interest in genetic, molecular and cellular mechanisms of aging rather than a cybernetic or systems approach (Sacher, 1968; Dayan, 1972; Timiras, 1972). Attempts to formulate only genetic and molecular hypotheses of aging for the brain a priori exclude reference to possibly equally important other levels of biological and social organization. The brain is uniquely characterized by tissue interdependence, organizational complexity, redundancy and environmental modifiability. This implies that environmental influences on the organization of the brain may be just as significant as the genetic, molecular and cellular changes currently considered as the basic or exclusive sources of biological aging (Strehler and Barrows, 1970; Medvedev, 1972; Orgel, 1973; Marx, 1974).

Since the foveal photoreceptors in the duplex retina of adult human and other diurnal primates are closely associated with high visual acuity and spectral sensitivity, observations were made on the pre- and postnatal morphologic development of the macula and fovea in the retina of the diurnal rhesus monkey. Histologic findings on the level of development of the retina at birth revealed a macula with the characteristic foveal depression. Observations on the ultrastructural development of the foveal photoreceptors revealed that their outer and inner segments were relatively well differentiated even at birth. An examination of the prenatal morphogenesis of the photoreceptors in the eye of the fetus indicated that the initial differentiation of the receptors may take place as early as 100 to 125 days after conception. However, the receptors in the specialized fovea continued to develop for 1 to 2 months after birth, whereas the photoreceptors outside the central region of the retina had completed their fine structural development at birth. By the end of the second month after birth, the macular and foveal areas essential for high visual acuity and spectral sensitivity appeared structurally well completed. In general, major maturational changes observable after birth were apparent predominantly in the pigment epithelium of the retina.