Male nuclei

As mentioned above, the true endosperm is derived from two polar nuclei of the ovule and one male nucleus. It is therefore at least a triploid tissue. 

Izquierdo M.A., Collado P., Segovia S., Guillamon A. and del Cerro M. (1992). Maternal behavior induced in male rats by bilateral lesions of the bed nucleus of the accessory olfactory tract. Physiol Behav 52, 707-712. 

Yokosuka M., Matsuoka M., Ohtani-Kaneko R., Iigo M., et al. (1999). Female-soiled bedding induced Fos immunoreactivity in the ventral part of the premammillary nucleus (PMv) of the male mouse. Physiol Behav 68, 257-261. 

The very beginning of the first mitotic cell cycle of the mouse embryo seems to be controlled by the mechanisms characteristic for both meiotic and mitotic cell cycles. Active MAP kinase, its substrate p90rsk and the CSF activity itself could influence the cellular processes within the one-cell embryo. Indeed, we have observed that despite the entry into the interphase (as judged by the low activity of MPF) some proteins are actively phosphorylated as during the meiotic M phase (e.g. 35 kDa complex Howlett et al 1986, Szollosi et al 1993), the nuclei and the microtubule interphase network start to form only 1.5 hours after activation (Szollosi et al 1993). This delay in the phenomena characteristic for the interphase could be linked to the mixed meiotic/mitotic character of this early period. This delay probably allows the correct transformation of the sperm nucleus into the male pronucleus. In species like Xenopus or Drosophila the transitional period between the meiotic and the mitotic cell cycle control is probably much shorter since it is proportional to duration of the short first cell cycle of these rapidly cleaving embryos. Mammalian embryos are perhaps the most suitable to study this transition because of the exceptionally long first embryonic cell cycle. 

Figure 7.4 Dose-response effects of MDMA on extracellular levels of endogenous 5-HT (left panel) and DA (right panel) in rat nucleus accumbens. Male rats undergoing in vivo microdialysis received i.v. injections of 1 and 3 mg/kg MDMA at 0 and 60 min, respectively. Dialysate levels of 5-HT and DA were assayed by HPLC-ECD. Data are mean SEM, expressed as pg/5 pi sample, for N = 6 rats/group. Baseline levels of 5-HT and DA were 0.22 0.03 and 1.44 0.24 pg/5 pi, respectively. Significant with respect to pre-injection control (P < 0.05 Duncan s). See Baumann et al.39 for methods.

Wood, R,I, and Coolen, L.M. (1997) Integration of chemosensory and hormonal cues is essential for sexual behaviour in the male Syrian hamster role of the medial amygdaloid nucleus, Neuroscience 78, 1027-35. 

Red blood cells are amongst the most numerous of the human cell lines an average healthy 70 kg male having a total of approximately 25 x cells in his 51 of blood. A typical red cell contains in excess of 600 million haemoglobin molecules which equates to a total of about 300 g of haemoglobin, an amount that is far greater than for any other protein in the body. The lack of a nucleus clearly indicates that red cells cannot divide and at the end of their life, worn out RBCs are removed by the cells of the reticuloendothelial system. Approximately 2% (5 x 1011) of the red cell number are removed and replaced by new ones each day. Haem synthesis is outlined later in this chapter and its catabolism is discussed in Chapter 6. 

More recent studies in Drosophila revealed that H3.3 also plays an important role in the male pronucleus after fertilization (Loppin et al. 2005). The loss of the H3.3 chaperone HIRA impairs the replacement of paternal non-histone proteins from the sperm nucleus with maternally provided histones including H3.3, while the maternal genome exclusively contains the canonical H3. Thus, H3.3 and its deposition factor HIRA function in early fertilization events and might have a role in imprinting in higher eukaryotes. 

Dahehour A, Quertemont E, De Witte P. 1994. Acute ethanol increases taurine but neither glutamate nor GABA in the nucleus accumbens of male rats a microdialysis study. Alcohol Alcohol 29(5) 485-487. 

Blaha V, Yang ZJ, et al (1998) Systemic nicotine administration suppresses food intake via reduced meal sizes in both male and female rats. Acta Medica41(4) 167-173 Blanchard BA, Steindorf S, et al (1993) Sex differences in ethanol-induced dopamine release in nucleus accumbens and in ethanol consumption in rats. Alcohol Cfin Exp Res 17(5) 968-973 Booze RM, Welch MA, et al (1999) Behavioral sensitization following repeated intravenous nicotine administration gender differences and gonadal hormones. Pharmacol Biochem Behav 64(4) 827-839... 

Rose JE, Levin ED (1991) Inter-relationships between conditioned and primary reinforcement in the maintenance of cigarette smoking. Br J Addict 86(5) 605-609 Rosecrans JA (1971) Elfects of nicotine on brain area 5-hydroxytryptamine function in male and female rats separated for differences of activity. Eur J Pharmacol 16(1) 123-127 Rosecrans JA (1972) Brain area nicotine levels in male and female rats with different levels of spontaneous activity. Neuropharmacology ll(6) 863-870 Rosecrans JA, Schechter MD (1972) Brain area nicotine levels in male and female rats of two strains. Arch Int Pharmacodyn Ther 196(l) 46-54 Saigusa T, Takada K, et al (1997) Dopamine efflux in the rat nucleus accumbens evoked by dopamine receptor stimulation in the entorhinal cortex is modulated by oestradiol and progesterone. Synapse 25(1) 37 3... 

Androgens and estrogens are, respectively, male and female sex hormones. They act through cytosolic receptors that, when activated, migrate to the nucleus and influence gene expression. 

Furukawa T, Manabe S, Watanabe T et al 1999 Daily fluctuation of hepatic P450 mono-oxygenase activities in male rats is controlled by the suprachiasmatic nucleus but remains unaffected by adrenal hormones. Arch Toxicol 73 367-372 Gillette MU 1986 The suprachiasmatic nuclei. Circadian phase-shifts induced at the time of hypothalamic slice preparation are preserved in vitro. Brain Res 379 176-181 Guo YF, Stein K 2003 Circadian rhythm in the cardiovascular system. Chronocardiology. jAm Heart J 145 779-786... 

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