A genetic linkage map of the laboratory rat, Rattus norvegicus.

We report the construction of the first complete genetic linkage map of the laboratory rat. By testing 1171 simple sequence length polymorphisms (SSLPs), we have identified 432 markers that show polymorphisms between the SHR and BN rat strains and mapped them in a single (SHR x BN) F2 intercross. The loci define 21 large linkage groups corresponding to the 21 rat chromosomes, together with a pair of nearby markers on chromosome 9 that are not linked to the rest of the map. Because 99.5% of the markers fall into one of the 21 large linkage groups, the maps appear to cover the vast majority of the rat genome. The availability of the map should facilitate whole genome scans for genes underlying qualitative and quantitative traits relevant to mammalian physiology and pathobiology.

Retinoic acid-induced tissue transglutaminase and apoptosis in vascular smooth muscle cells.

Retinoids exert antiproliferative and prodifferentiating effects in vascular smooth muscle cells (SMCs) and reduce neointimal mass in balloon-injured blood vessels. The mechanisms through which retinoids carry out these effects are unknown but likely involve retinoid receptor-mediated changes in gene expression. Here we report the cloning, chromosomal mapping, and biological activity of the retinoid-response gene rat tissue transglutaminase (tTG). Northern blotting studies showed that tTG is rapidly and dose-dependently induced in a protein synthesis-independent manner after stimulation with the natural retinoid all-trans retinoic acid (atRA). The induction of tTG was selective for atRA and its stereoisomers 9-cis and 13-cis RA, because little or no elevation in mRNA expression was observed with a panel of growth factors. Western blotting and immunofluorescence confocal microscopy showed an accumulation of cytosolic tTG protein after atRA stimulation. Radiolabeled cross-linking studies revealed a corresponding elevation in in vitro tTG activity. The increase in tTG activity was reduced in the presence of 2 distinct inhibitors of tTG (monodansylcadaverine and cystamine). atRA-induced tTG mRNA and protein expression were followed by a significant elevation in SMC apoptosis. Such retinoid-induced programmed cell death could be partially inhibited with each tTG inhibitor and was completely blocked when both inhibitors were used simultaneously. These results establish a role for atRA in the sequential stimulation of tTG and apoptosis in cultured SMCs. atRA-mediated apoptosis in SMCs seems to require the participation of active tTG, suggesting a potential mechanistic link between this retinoid-inducible gene and programmed cell death.

Expression and cloning of complementary DNA for a human enzyme that repairs O6-methylguanine in DNA.

A cell line with an increased resistance to alkylating agents and an extremely high level of O6-methylguanine-DNA methyltransferase activity was isolated after transfection of methyltransferase-deficient Mer- cells with a cDNA library, prepared from methyltransferase-proficient human Mer+ (Raji) cells. Sodium dodecyl sulfate/polyacrylamide gel electrophoresis analysis revealed that a protein, with a molecular weight of approximately 25,000, accepted 3H label from DNA that had been treated with [3H]methylnitrosourea. Since the cDNA for methyltransferase was integrated into the chromosomal DNA, it was recovered by using the polymerase chain reaction. When the cDNA placed in an expression vector p500 was introduced into Mer- cells, the cells acquired an increased resistance to alkylating agents and exhibited a high level of O6-methylguanine-DNA methyltransferase activity. From the transformants the cDNA could be recovered as a part of the autonomously replicating plasmid. The nucleotide sequence of the cDNA was determined, and an open reading frame comprising 207 amino acid residues was found. The molecular weight of methyltransferase, calculated from the predicted amino acid sequence, was 21,700. The predicted amino acid sequence of the human methyltransferase exhibits an intensive homology with those of the bacterial counterparts, Ada and Ogt proteins of Escherichia coli and Dat protein of Bacillus subtilis, especially around possible methyl acceptor sites.

Expression of the ada gene of Escherichia coli in response to alkylating agents. Identification of transcriptional regulatory elements.

Ada protein plays a central role in the regulatory synthesis of DNA repair enzymes, following exposure of Escherichia coli to alkylating agents. Methyl groups of alkylated DNA are transferred to Ada protein by its own methyltransferase activity and the methylated Ada protein then acts as a positive regulator to overproduce the ada and related gene products. To elucidate regulatory mechanisms for the expression of the ada gene by its own product, we analyzed the ada promoter region by random and site-directed mutagenesis. A series of deletion analyses revealed that a sequence up to 53 nucleotides upstream from the transcription initiation site is required for the controlled expression of the ada gene. Libraries of base substitution mutants were constructed by synthesizing oligonucleotides corresponding to the ada promoter region in the presence of a small amount of all possible sets of nucleotides. Internal deletion and insertion mutants were also constructed with the use of synthetic oligonucleotides. Using these mutants, the -10 and the -35 boxes of the promoter as well as the ada regulatory sequence were identified, the latter being an eight-nucleotide sequence, AAAGCGCA. A six-nucleotide stretch between the regulatory sequence and the -35 box, also affected levels of expression of the gene. When the promoter DNAs derived from wild type or base substitution mutants that showed normal expression in vivo were used as templates for transcription in vitro, the ada-specific RNA was formed in the presence of a methylated form of Ada protein. With the DNAs derived from mutants of defective type as templates, no or relatively small amounts of the RNA were synthesized. Some base substitution mutants showed a constitutive expression of the gene in vivo, but this observation did not reconcile with findings in experiments in vitro.

Angiotensin in the nucleus tractus solitarii contributes to neurogenic hypertension caused by chronic nitric oxide synthase inhibition.

Activation of the sympathetic nervous system and renin-angiotensin system has been suggested to contribute to the hypertension caused by chronic nitric oxide synthase inhibition. The aim of the present study was to determine whether angiotensin within the nucleus tractus solitarii (NTS) plays a role in activation of the sympathetic nervous system in this model. Rats were treated with N(omega)-nitro-L-arginine methyl ester (L-NAME, 100 mg. kg(-1). d(-1) in drinking water) for 2 weeks. Experiments were performed on anesthetized rats with denervated arterial and cardiopulmonary baroreceptors. Arterial pressure, heart rate, and renal sympathetic nerve activity (RSNA) were measured. Microinjection of an angiotensin II type 1 (AT(1)) receptor antagonist (CV11974) or an angiotensin II type 2 (AT(2)) receptor antagonist (PD123319) into the depressor region within the NTS (identified by prior injection of L-glutamate) was performed. Microinjection of CV11974, but not of PD123319, produced greater decreases in arterial pressure, heart rate, and RSNA in L-NAME-treated rats than in control rats. The administration of hexamethonium resulted in a larger fall in arterial pressure in L-NAME-treated rats than in control rats. The ACE mRNA level in the brain stem was greater in L-NAME-treated rats than in control rats. These results suggest that increased sympathetic nerve activity plays a role in hypertension caused by chronic nitric oxide synthase inhibition and that activation of the renin-angiotensin system in the NTS is involved at least in part in this increased sympathetic nerve activity via AT(1) receptors.

Cloning, characterization, and genetic mapping of the rat type 2 angiotensin II receptor gene.

The renin-angiotensin system plays an important role in blood pressure homeostasis, but the contribution of the type 2 angiotensin II receptor (AT2R) is still unclear. The reports that the AT2R gene has been mapped to the X chromosome in human and rat and the previous report of a gene, Bp3, on the X chromosome responsible for an increase in blood pressure have suggested that the rat AT2R gene (Agtr2) could be this gene. To elucidate whether Agtr2 is Bp3, Agtr2 was cloned. A simple sequence repeat in the 3'-flanking region of this gene was identified and used as a genetic marker to map Agtr2 to the X chromosome at 18.1 cM distal to the androgen receptor locus. This map position is outside the confidence interval reported for Bp3, demonstrating that Agtr2 cannot be Bp3. However, these data will enhance the research into the AT2R biology as well as the study of the X chromosome.

Transfer of a salt-resistant renin allele raises blood pressure in Dahl salt-sensitive rats.

To evaluate the role of the renin gene in the development of hypertension in Dahl salt-sensitive rats (SS/Jr/Hsd), we derived a congenic strain of rats homozygous for the salt-resistant renin allele (S/renrr) and compared them with a control strain homozygous for the salt-sensitive renin allele (S/ren(ss). Mean arterial pressure was significantly higher in 12-week-old S/renrr rats fed a high salt (8.0%) diet for 3 weeks than in S/ren(ss) rats or in SS/Jr/Hsd rats rederived from the foundation colony we used to generate the cogenic strain (195 +/- 3 [n = 49] versus 168 +/- 3 [n = 17] or 161 +/- 3 [n = 16] mm Hg). Mean arterial pressure was also higher in S/renrr rats than in S/ren(ss) rats raised from birth on either a very low salt (0.1%) diet (119 +/- 9 [n = 6] versus 100 +/- 7 [n = 7] mm Hg) or a low salt (0.4%) diet (143 +/- 1 [n = 22] versus 117 +/- 3 [n = 10] mm Hg). Plasma renin activity of S/renrr rats was significantly higher than that of S/ren(ss) rats fed a very low salt diet (5.7 +/- 2.0 versus 1.8 +/- 0.3) ng angiotensin l/mL per hour), a low salt diet (4.4 +/- 1.0 versus 1.1 +/- 0.3), or a high salt diet (1.5 +/- 0.2 versus 0.9 +/- 0.1). Urinary protein excretion was greater in S/renrr rats than in S/ren(ss) rats fed a high salt diet (244.2 +/- 48.5 versus 43.6 +/- 19.5 mg/24 h), and this was associated with significant reductions in renal blood flow (3.3 +/- 0.6 versus 4.6 +/- 0.5 mL/min per gram kidney weight) and glomerular filtration rate (0.49 +/- 0.11 versus 0.82 +/- 0.08 mL/min per gram kidney weight). Captopril (20 mg/kg i.v.) had no effect on blood pressure in S/ren(ss) rats fed a low salt diet, but it lowered blood pressure by 20 mm Hg in S/ren(rr) rats to the same level seen in untreated S/ren(ss) rats. Chronic administration of captopril (5 mg/100 mL drinking water) reduced blood pressure in S/renrr rats fed a high salt diet (170 +/- 5 mm Hg) to the same level seen in untreated S/ren(ss) rats, whereas it had no significant effect on blood pressure in S/ren(ss) rats. These results indicate that transfer of a salt-resistant renin allele to SS/Jr/Hsd rats raises plasma renin activity and augments the severity of hypertension and renal disease.

Investigation of the phenylethanolamine N-methyltransferase gene as a candidate gene for hypertension.

Genetic mapping studies have located a gene, Bp1, that accounts for approximately 30% of the genetic variation in the stroke-prone spontaneously hypertensive rat (SHRSP) to a region on chromosome 10 containing the angiotensin-converting enzyme gene. In humans, the gene encoding phenylethanolamine N-methyltransferase (PNMT) was localized near the angiotensin-converting enzyme gene on human chromosome 17. Since most of human chromosome 17 is known to be homologous to rat chromosome 10 and PNMT is known to play a role in blood pressure homeostasis, we reasoned (1) that the rat gene encoding PNMT (Pnmt) may reside on chromosome 10 within the confidence interval containing Bp1 and (2) that Pnmt is a good candidate gene for Bp1. With the use of a somatic cell hybrid panel and genetic mapping techniques, Pnmt mapped within the confidence interval that contains Bp1. To examine further this possibility of Pnmt as a candidate for Bp1, we cloned and characterized Pnmts of the original parental strains, the Wistar-Kyoto rat and SHRSP from the Heidelberg colony. We did not identify any sequence differences between the Wistar-Kyoto rats and SHRSP in the primary structure, in 1077 bp of the 5'-flanking region, or in the 256-bp 3'-end region, making Pnmt an unlikely gene for the genetic basis of salt-loaded hypertension.

Genomic organization and polymorphism of human angiotensin II type 2 receptor: no evidence for its gene mutation in two families of human premature ovarian failure syndrome.

Angiotensin II type 2 (AT(2)) receptor is highly expressed in the fetal tissues and decreases rapidly after birth. AT(2) receptor is re-expressed in the adult atretic ovarian follicles. Recently, it has been reported that AT(2) receptor mediates apoptosis. Primarily, we have cloned human AT(2) receptor cDNA and mapped it to the X-chromosome. To further analyze the organization and function of the AT(2) receptor gene, in this study we cloned the human AT(2) receptor genomic DNA. Human AT(2) receptor gene is composed of three exons and two introns. Primer extension analysis revealed a putative transcription initiation site at 24 bp downstream from TATA box. Furthermore, we identified a polymorphism (C-A) in 3' untranslated region of exon 3, which may be a useful genetic marker for genetic analysis of human X-linked inherited disease. In this study, we postulated that the patients with premature ovarian failure, which has been reported to be linked with X-chromosome abnormality, have AT(2) receptor mutation that may contribute to the early onset of atresia. We examined the entire coding sequence of this receptor in two different families of sisters with premature ovarian failure (POF) but found no changes in nucleotide sequences.

Subarachnoid hemorrhage due to rupture of infundibular dilation of a circumflex branch of the posterior cerebral artery: case report.

The authors describe a rare case in which an infundibular dilation at the origin of a circumflex branch of the P1 segment of the posterior cerebral artery caused subarachnoid hemorrhage. Wrapping was performed by a subtemporal approach in the delayed stage. At the time of surgery, the rupture point was found in the infundibular dilation.

Sinus histiocytosis with massive lymphadenopathy: a case of multiple dural involvement.

An exceptional case of Rosai-Dorfman disease (sinus histiocytosis with massive lymphadenopathy) arising from the meninges in a 60-year-old Japanese man is presented. Computerized tomographic scans and magnetic resonance images demonstrated well-circumscribed tumorous lesions that were homogeneously enhanced with contrast medium. Systemic examination revealed no abnormalities except for a cervical lymphadenopathy and diabetes mellitus. Microscopic examination of the resected specimens showed proliferated histiocytosis and infiltration of plasma cells and lymphocytes. The histology was characterized by the presence of histiocytes demonstrating lymphophagocytosis and immunoreactivity for S-100 protein staining. Immunohistochemical studies and electron microscopy were useful in confirming the diagnosis. The clinical and histopathological features of this disease are discussed.

Unilateral tongue atrophy due to an enlarged emissary vein in the hypoglossal canal.

A 16-year-old girl presented to our clinic with right-sided tongue atrophy and fasciculations of 1-year duration. Enlargement of the outer opening of the hypoglossal canal was reveal by conventional and computed tomography of the skull. Magnetic resonance imaging disclosed an enlarged venous system extending from the jugular vein to the internal jugular vein on the right, with low signal density suggestive of a flow void. A right-sided occipital craniotomy was performed. When the hypoglossal canal was opened, an enlarged emissary vein compressing the hypoglossal nerve was identified. This is the first reported case of unilateral tongue atrophy and an enlarged hypoglossal canal due to an enlarged emissary vein.

Juxta-dural ring aneurysms of the internal carotid artery.

The terminology of juxta-dural ring aneurysms of the internal carotid artery is reviewed historically with special reference to those aneurysms protruding ventrally. The first description of such cases was made by Drake as exceptional examples of carotid-opthalmic aneurysms. Yasargil and Fox termed them ventral (inferior) internal carotid artery aneurysms. The term (ventral) paraclinoid aneurysms was coined by Nutik. We introduce the concept of carotid cave aneurysms. The name superior hypophyseal artery aneurysms was proposed by Day. Other related terminologies by various authors are also described.

A classification of juxta-dural ring aneurysms with reference to surgical anatomy.

We report a subgroup of internal carotid artery (ICA) aneurysms located near the carotid ring which we call juxtadural ring aneurysms. These aneurysms are classified into three types: paraclinoid intradural, carotid cave and infraclinoid extradural aneurysms. The paraclinoid intradural aneurysms arise from the ICA distal to the origin of the ophthalmic artery and are close to the dural ring, which may include some so-called carotid-ophthalmic aneurysms. The carotid cave aneurysms are located in the carotid cave which is seated in the infraclinoid carotid groove and proximal to the origin of the ophthalmic artery. They are located at the angiographical genu and in the intradural space anatomically. The infraclinoid extradural aneurysms are located close to the dural ring extradurally in the infraclinoid carotid groove sinus, a peripheral venous space of the cavernous sinus. The infraclinoid extradural aneurysms should be differentiated from aneurysms in the cavernous sinus, because they are located in the infraclinoid carotid groove sinus.

Surgical resection of cerebral arteriovenous malformation combined with pre-operative embolisation.

To assess the importance of pre-operative embolisation, 27 cases of cerebral artriovenous malformation (AVM) treated in this institute between July 1994 and October 1998 were analysed. The patients' ages ranged from 3 to 70 years (average 36.9) with a follow-up period of 1-41 months (average 19.2). The patient presented with haemorrhage in 21 cases and seizure in five. In 21 of 27 cases, surgical resection of a nidus was performed, gamma knife therapy was applied in three and conservative therapy was chosen in three. Of 21 cases treated surgically, total removal was achieved in 19 cases and a residual nidus was seen in one (a large basal ganglia AVM). In the remaining case, postoperative angiography was not available. Pre-operative embolisation followed by surgical resection of the nidus was performed in seven cases in which there was a large AVM. A volume index was calculated to indicate the size of the nidus using X x Y x Z, where X is the maximum diameter (cm) of the nidus on the lateral angiogram, Y is the diameter (cm) perpendicular to X and Z is the maximum diameter (cm) on the anteroposter or angiogram. The index averaged 45.9 for the cases in which pre-operative embolisation was performed, while it was 5.6 in the cases without embolisation. Pre-operative embolisation was performed to reduce the nidus flow as much as possible, to prevent overload to the surrounding structures. At surgery, the nidus was resected from the surrounding tissue and care was taken not to enter the nidus. Postoperatively, the systolic blood pressure was maintained at 90-100 mmHg for several days in the intensive care unit. The results were excellent in 15 cases, good in three (hemiparesis due to the initial haemorrhage remained in all three), fair in one (a patient with a severe subarachnoid haemorrhage). Two patients died (acute pulmonary oedema and severe meningitis). Minor postoperative bleeding or oozing was seen in three cases. In conclusion, reducing the shunt flow through a nidus in a step-wise fashion with pre-operative embolisation of a large AVM seems to be quite helpful in preventing postoperative haemodynamic overload to the surrounding brain. It is also important not to enter the nidus when it is removed at surgery. This helps to prevent intraoperative and/or postoperative bleeding, and led to successful total removal of the nidus with a good postoperative course.

Non-ruptured large dorsal internal carotid artery aneurysm presenting with temporal quadrantanopsia.

A 63-year-old woman presenting with temporal lower quadrantanopsia of the right eye was found to have a large dorsal internal carotid artery aneurysm. Large dorsal aneurysms of the internal carotid artery are rare. Lateral compression of the optic nerve by the aneurysm might damage the optic nerve at the medial side of the right optic foramen. Direct clipping surgery was performed uneventfully. Since the dome of the aneurysm was buried in the frontal lobe and also attached to the anterior skull base, a careful approach to the aneurysm with removal of the anterior clinoid process and drilling into the planum sphenoidale around the aneurysm dome was needed. The surgical strategy is discussed.

Effect of protein intake level on urinary energy/nitrogen ratio in Japanese.

Urinary energy/nitrogen ratios were determined in 179 female and 14 male subjects given protein from various sources and at various intake levels. The ratio decreased with increasing protein intake from zero to 1 g/kg/day but was constant when protein intake was between 1 to 1.8 g/kg/day. The ratio was not affected by the variety of protein source. There was no difference between the data for semisynthetic diet and conventional diet. Mean values and standard deviations of the ratio in men and women given the diet containing 1.0 to 1.8 g protein/kg/day were 9.06 +/- 0.56 (n = 14) and 8.19 +/- 0.81 (n = 37) kcal/kg N, respectively. The difference between two figures in men and women was significant (p less than 0.05). The mean values of urinary E/N ratio actually measured did not approach those of urea (5.34 kcal/g N), the principal nitrogenous compound in urine, the proportion of which increased at higher protein intake level. Characteristically high ratios were obtained in the ma-konbu (Laminaria japonica) and enokitake (Flammulina velutipes) diet groups. The results suggest that urinary energy originates not only from nitrogen-containing compounds but also from other organic compounds containing no nitrogen. Therefore, further investigation is necessary to evaluate the urinary E/N ratio applicable to the urinary loss of incompletely oxidized nitrogenous compounds.

Utilization and requirement of egg protein in Japanese women.

Utilization and requirement of egg protein in Japanese women with two levels of energy intake were estimated. In experiment 1, fifteen female students were given semi-purified diet containing whole egg as the sole nitrogen source for 12 days. Nitrogen intakes were 50 for five, 75 for two and 100 mg N/kg for eight subjects. Habitual energy intake was determined individually by detailed inquiry about the foods consumed before the experiment was started. Mean energy intake was 33 kcal/kg. In experiment 2, eighteen other subjects were given the same diet containing four intake levels of egg protein (30, 50, 75, 100 mg N/kg) with an energy intake of about 100 kcal/day added to that calculated by the food intake inquiry. The mean energy intake was 37 kcal/kg. The total nitrogen contents of the experimental diet, urine and feces were analyzed and the nitrogen balance was estimated from these figures. Significant rectilinear relations were found between nitrogen intake (X, mg N/kg) and balance (Y, mg N/kg). The regression equations were: Experiment 1: Y = 0.256X - 34.4 (n = 15, r = 0.742) Experiment 2: Y = 0.326X - 29.7 (n = 18, r = 0.645) The maintenance intakes of whole egg protein for apparent nitrogen equilibrium were calculated to be 134 and 91 mg N/kg with energy intakes of 33 and 37 kcal/kg, respectively. Net protein utilization (NPU) and digestibility of egg protein were calculated using the obligatory N losses previously determined in Japanese women. The NPUs at the maintenance level of egg protein with energy intakes of 33 and 37 kcal/kg were estimated as 31 and 47, respectively. The mean digestibility of egg protein was 96%.

Obligatory N loss and utilization of egg and rice mixed protein in young japanese women.

Obligatory urinary and fecal N losses in young Japanese women were evaluated and the effect of energy intake on the utilization of rice and egg mixed protein was investigated in subjects receiving a low protein diet. Seven female students were given a protein-free diet for ten days. Feces and 24-h urine samples were collected throughout the period and their nitrogen contents were analyzed. Basal metabolism was measured and the lean body mass was calculated from urinary creatinine excretion by the equation of Forbes. The mean weight loss of the 7 subjects during the ten days was 1.5 kg, the mean obligatory urinary N loss was 32.3 +/- 5.9 mg/kg body weight, 1.67 +/- 0.45 mg/kcal basal metabolism, or 1.68 +/- 0.32 g/g creatinine, and the mean obligatory fecal N loss was 10.1 +/- 2.0 mg/kg body weight, or 0.51 +/- 0.08 mg/kcal basal metabolism. In a second experiment, 17 female subjects were divided into three groups with an energy intake of about 35, 42, 46 kcal/kg BW, respectively. During the 7-day experimental period, they were given a low protein diet containing 250 g of rice and 125 g of whole egg. The nitrogen contents of the 24-h urine samples and feces collected were analyzed and the nitrogen balance was calculated as the difference between N intake and urinary and fecal N excretion. Subjects with an energy intake of 35 kcal/kg BW had a negative N balance, while subjects with an intake of 46 kcal/kg BW achieved an apparent positive N balance. The NPU values of rice and egg mixed protein with energy intake of 35, 42, 46 kcal/kg BW were calculated from the N balance data and the values for obligatory urinary and fecal N losses in the first experiment as 25, 37 and 54, respectively.

Utilization of soy protein isolate mixed with rice protein in Japanese women.

Utilization and requirement of soy protein isolate (SPI) and SPI-rice combination were examined in twenty-five female students. After 1 day on protein-free diet, each subject received a low-protein diet for 10 days. The protein sources were SPI for ten subjects and SPI-rice combination, in which the ratio of two proteins was 6:4, for fifteen subjects. The nitrogen intakes were about 45, 65 and 85 mg/kg in both the two series of experiments. Energy intake was at an approximate maintenance level of 36.1 +/- 3.0 kcal/kg. Apparent nitrogen balance improved with increase in nitrogen intake. The regression equations between nitrogen intake (X, mg/kg) and balance (Y, mg/kg) are shown in the following: SPI: Y = 0.411 X - 40.8 (n = 10, r = 0.812) SPI and rice protein: Y = 0.392 X -32.7 (n = 15, r = 0.739) From the above equations, the maintenance intakes of SPI and SPI-rice combination for an apparent nitrogen equilibrium were calculated to be 99 and 83 mg N/kg, respectively. Digestibilities were 98.2 +/- 5.0% for SPI and 93.1 +/- 6.1% for SPI-rice combination. The NPUs of SPI at intake levels of 40, 60 and 80 mg N/kg were 47 +/- 24 (n = 4), 49 (n = 2) and 44 +/- 3 (n = 4), respectively. The NPUs of SPI and rice mixed protein at intake levels of 45, 70 and 90 mg N/kg were 67 +/- 13 (n = 5), 51 +/- 7 (n = 5) and 54 +/- 12 (n = 5), respectively. It was concluded from the present study that both SPI and the SPI-rice combination had a high nutritive efficiency comparable with that of egg protein.