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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.

The fatty acid composition of central nervous system lipids is largely independent of the dietary fat except for docosahexanoic acid (22:6ω3) and its precursors, mainly linolenic acid (18:3ω3). Ingestion of these lipids increases peroxidizability of neuronal phospholipids by displacing 22:5ω6 with 22:6ω3. Since lipofuscin (age pigment) is formed by oxidative polymerization of lipid and protein it seemed likely that increases in dietary 22: 6ω3 and/or peroxidizability of the dietary lipids might enhance lipofuscin accumulation. To evaluate these possibilities groups of male Charles River CD strain rats were fed a commercial diet, or semi-synthetic diets containing either 5%w (percent by weight) lard, 20%w olive oil, or 20%w safflower oil for periods up to 28 months of age; the amount of 22:6ω3 in lard is small, but considerably more than that of 22:6ω3 plus its precursors in olive oil or safflower oil. At 24 months of age the lipofuscin content of hippocampal neurons of rats fed the lard diet was significantly greater than for the control, olive oil or safflower oil groups; there was no significant difference between the latter two groups. Thus lipofuscin accumulation in hippocampal neurons was associated with increases in neuronal content of 22:6ω3 and not with the gross peroxidizability of the dietary lipid.

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).

Alcoholism is one of the major health problems of the world. In the United States, it is believed that between 6 to 8 million adults of the total population of 220 million may be addicted to alcohol. It is generally overlooked that in terms of addiction, alcohol is of far greater importance than all of the other drugs combined (Rubin and Lieber, 1971). Alcoholism occurs as a consequence of chronic drinking and some form of predisposition, either psychological, biochemical, or genetic in nature. Recently, it has been shown that alcoholism is a form of drug addiction according to pharmacological criteria of tolerance and dependence (Mendelson and Mello, 1969). Various genetic and other psychosocial factors, such as sex, age, education, occupation, income and religion may all play an important role in the drinking habits of a population. According to one survey (Cahalan and Cisin, 1968), older people generally appear to drink less than younger people. However, senescence in some individuals is often associated with many adaptational and behavioral problems such as depression and anxiety brought on by financial insecurity, disability, or death of a family member (Busse and Pfeiffer, 1969). Such conditions may frequently lead to excessive drinking in some members of an older population.

In the past decade, there has been a significant increase in man’s interest in the phylogenetic aspects of behavior, physiology, biochemistry and anatomy. This interest may reflect an attempt to gain a more comprehensive understanding of man himself, in comparative perspective. Specific interests include; examination of the evolution of the vertebrate brain and cerebral cortex (Nauta and Karten, 1970), evolution of the nervous system and behavior (Hodos, 1970), evolution of primate behavior (Washburn and Harding, 1970), the primate brain and maximum life span (Sacher, 1973), evolution of primate behavior and the emergence of human culture (Lancaster, 1975).

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).

As one of the neurosciences, psychology is generally defined as the objective study of behavior. Its major areas of interest include: sensory processes and psychophysics, learning, intelligence, personality and group dynamics (Kimble and Garmezy, 1968). A great deal of human and animal behavior can be explained by laws and theories in terms of stimulus (S) and response (R) relations without reference to any specific biological bases of behavior within the organism (O). According to this behavioristic (S-O-R) view, as intervening variables, psychological events are inferred from objectively described observed behavior made in response to environmental stimuli rather than introspective descriptions of experience. More recently, there has been an increasing recognition within all disciplines comprising “Neuroscience” that nothing may be more certain than that all behavior is a product of the nervous system. As a branch of psychology, neuropsychology has been defined as the objective study of the relationship between brain and behavior. Many neurobiologists believe that basic to a more comprehensive and fundamental understanding or interpretation of the behavior of man throughout life, from a simple knee-jerk reflex to the creation of science and art, lies in the understanding of the structures and functions of the nervous system.

Fundamental Criteria, Data or Facts of Biological Aging. The deterioration or “aging” of objects, animals and human beings with the passage of time is one of the most universal, inevitable and conspicuous features or characteristics observable in nature. With the passage of time, changes occur in the properties, organization or composition of all objects and living systems. The progressive alterations with the passage of time can be imperceptible, gradual and proceed at certain rates or they can become abrupt or sudden and terminate in permanent change in state or “death” as clearly demonstrable “end points” of a system. The measurement of the rates of gradual changes may be more difficult, particularly for long-lived biological systems, even under steady-state environmental conditions. Consequently, such easily-recognizable end points of biological aging as death and the ensuing mortality distributions of a sample from a larger population are the most frequently used and convenient starting points or criteria of biological aging. If the end point in a sample from a population is an abrupt change in state or death, the percentage of individual members of an original sample remaining or surviving can be plotted statistically as a function of time.

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.

Stimulated in part by rapid and parallel advances in biochemistry and neurobiology, the field of neurochemistry has been characterized by a remarkable expansion in the past decade. Despite this rapid advance, however, research on the neurochemistry of aging in man and other primates has been sparse and inconclusive. This paucity of research can be attributed in part to the long life span of man and the primates and in part to the broad, diversified, and exploratory focus on such biological mechanisms of aging as the extracellular components collagen and elastin, the search for age changes in particular cell types, tissue, or organs as a whole, and more recently the neuromolecular emphasis on age differences in a variety of intracellular organelles.

Spontaneous drug-seeking behavior was established in 3 out of 4 rhesus monkeys that were given unrestricted access to morphine and placebo solutions. The monkeys were kept in their home cages throughout the experiment and were not subjected to conditions of stress; prior addiction was not established by the usual injection procedures. The animals became physically dependent on the drug and showed abstinence symptoms when injected intramuscularly with nalorphine (N-allyl normorphine hydrochloride). This method may be useful for studying individual differences in susceptibility to drug abuse.