Title: Nasal nitric oxide in man

Authors: Lundberg JO, Weitzberg E.

Journal: Thorax. 1999 Oct;54(10):947-52. doi: 10.1136/thx.54.10.947. PMID: 10491460; PMCID: PMC1745376.

Link to full text: Nasal nitric oxide in man

Abstract: The past decade has witnessed an explosion in the interest of biologists in the gas nitric oxide (NO). This highly reactive free radical, first considered only a noxious air pollutant, is pro duced in mammalian cells by specific enzymes and is believed to play a vital role in many bio logical events including regulation of blood flow, platelet function, immunity, and neurotransmission. Direct measurement of NO in biological tissues is difficult to perform because this gas reacts rapidly with, for example, haemoglobin or other Fe2+ containing proteins. It is therefore often necessary to rely on indirect measurements in order to detect NO synthesis in vivo. Unlike the situation in most biological tissues where NO is rapidly destroyed, in the gas phase NO is fairly stable at low concentrations. NO produced in superficial structures of hollow organs will diffuse into the lumen and thus be detectable in gas collected from such organs. The presence of NO in exhaled breath of humans was first demonstrated by Gustafsson et al in 1991. Later studies clearly showed that, in healthy controls at rest, almost all NO found in exhaled air originates from the upper airways with only a minor contribution from the lower respiratory tract and the lungs.

Title: Inhalation of nasally derived nitric oxide modulates pulmonary function in humans

Authors: Lundberg JO, Settergren G, Gelinder S, Lundberg JM, Alving K, Weitzberg E.

Journal: Acta Physiol Scand. 1996 Dec;158(4):343-7. doi: 10.1046/j.1365-201X.1996.557321000.x. PMID: 8971255.

Link to PubMed: Inhalation of nasally derived nitric oxide modulates pulmonary function in humans

Abstract: The vasodilator gas nitric oxide (NO) is produced in the paranasal sinuses and is excreted continuously into the nasal airways of humans. This NO will normally reach the lungs with inspiration, especially during nasal breathing. We wanted to investigate the possible effects of low-dose inhalation of NO from the nasal airways on pulmonary function. The effects of nasal and oral breathing on transcutaneous oxygen tension (tcPO2) were studied in healthy subjects. Furthermore, we also investigated whether restoring low-dose NO inhalation would influence pulmonary vascular resistance index (PVRI) and arterial oxygenation (PaO2) in intubated patients who are deprived of NO produced in the nasal airways. Thus, air derived from the patient's own nose was aspirated and led into the inhalation limb of the ventilator. In six out of eight healthy subjects tcPO2 was 10% higher during periods of nasal breathing when compared with periods of oral breathing. In six out of six long-term intubated patients PaO2 increased by 18% in response to the addition of nasal air samples. PVRI was reduced by 11% in four of 12 short-term intubated patients when nasal air was added to the inhaled air. The present study demonstrates that tcPO2 increases during nasal breathing compared with oral breathing in healthy subjects. Furthermore, in intubated patients, who are deprived of self-inhalation of endogenous NO. PaO2 increases and pulmonary vascular resistance may decrease by adding NO-containing air, derived from the patient's own nose, to the inspired air. The involvement of self-inhaled NO in the regulation of pulmonary function may represent a novel physiological principle, namely that of an enzymatically produced airborne messenger. Furthermore, our findings may help to explain one biological role of the human paranasal sinuses.

Title: Impact of nasal polyposis on erectile dysfunction

Authors: Gunhan K, Zeren F, Uz U, Gumus B, Unlu H.

Journal: Am J Rhinol Allergy. 2011 Mar-Apr;25(2):112-5. doi: 10.2500/ajra.2011.25.3585. PMID: 21679515.

Link to PubMed: Impact of nasal polyposis on erectile dysfunction

Abstract:
Background: Our male patients with chronic rhinosinusitis with nasal polyposis (NP) declare a better sexual function after functional endoscopic sinus surgery (FESS) with polypectomy. This study was planned to conduct the first prospective, controlled trial evaluating the possible relation between erectile dysfunction (ED) and NP by subjective and objective parameters.

Methods: Thirty-three male patients with NP and thirty randomly selected male control subjects were evaluated. All subjects underwent assessments of nasal endoscopy, rhinomanometry, body mass index (BMI), Epworth Sleepiness Scale, full in-laboratory polysomnograpy and serum levels of glucose, thyroid hormones, lipid profile, and testosterone. ED was evaluated by the erectile function domain of the International Index of Erectile Function (IIEF-EF) subjectively and nocturnal penile tumescence (NPT) objectively. The NP group was reassessed 6 months after FESS.

Results: The mean age, BMI, and laboratory tests of the patients and the control subjects had no significant difference. The well-recognized risk factors for ED were eliminated. Preoperative evaluation of the patients revealed that ED was present in 34 and 24% of the patients by IIEF-EF and NPT, respectively, which was significantly higher than the control group (p = 0.009 and p = 0.018, respectively). There was a significant improvement of ED in the assessment of IIEF-EF and NPT postoperatively (p = 0.014 and p = 0.037, respectively).

Conclusion: ED was determined in a high percentage of patients with NP and significantly ameliorated after FESS. NP might present a risk factor in the development of ED.

Title: Chronic Rhinosinusitis Associated with Erectile Dysfunction: A Population-Based Study

Authors: Tai SY, Wang LF, Tai CF, Huang YT, Chien CY.

Journal: Sci Rep. 2016 Aug 31;6:32195. doi: 10.1038/srep32195. PMID: 27578370; PMCID: PMC5006045.

Link to full text: Chronic Rhinosinusitis Associated with Erectile Dysfunction: A Population-Based Study

Abstract: Few studies have investigated the relationship between chronic rhinosinusitis (CRS) and erectile dysfunction (ED). This case-control study aimed to investigate the association between CRS and the risk of ED in a large national sample. Tapping Taiwan's National Health Insurance Research Database, we identified people 30 years or older with a new primary diagnosis of CRS between 1996 and 2007. The cases were compared with sex- and age-matched controls. We identified 14 039 cases and recruited 140 387 matched controls. Both groups were followed up in the same database until the end of 2007 for instances of ED. Of those with CRS, 294 (2.1%) developed ED during a mean (SD) follow-up of 3.20 (2.33) years, while 1 661 (1.2%) of the matched controls developed ED, mean follow up 2.97 (2.39) years. Cox regression analyses were performed adjusting for sex, age, insurance premium, residence, hypertension, hyperlipidemia, diabetes, obesity, coronary heart disease, chronic kidney disease, chronic obstructive pulmonary disease, asthma, allergic rhinitis, arrhythmia, ischemic stroke, intracerebral hemorrhage, and medications. CRS was revealed to be an independent predictor of ED in the fully adjusted model (HR = 1.51; 95% CI = 1.33-1.73; P < 0.0001).

Title: Love Stinks: The Association between Body Odors and Romantic Relationship Commitment

Authors: Keaveny M, Mahmut MK.

Journal: Brain Sci. 2021 Nov 17;11(11):1522. doi: 10.3390/brainsci11111522. PMID: 34827521; PMCID: PMC8615518.

Link to full text: Love Stinks: The Association between Body Odors and Romantic Relationship Commitment

Abstract: Anecdotal reports indicate that women dislike their partner's body odor (BO) during the breakdown of a relationship; however, whether disliking a partner's BO is associated with intentions to break up has not been empirically tested. Therefore, the aim of the current study was to investigate, for the first time, whether disliking one's partner's BOs is associated with experiencing lower commitment to a romantic relationship. Eighty participants (48 partnered, 32 single and previously partnered) completed self-report questionnaires about their current or previous romantic relationship and the amount of exposure to-and hedonic ratings of-their current or former partner's BOs. Olfactory function was also tested, and participants smelled and rated various pieces of clothing imbued with a stranger's BO. The results demonstrated that for participants who had experienced a breakup, historically higher levels of relationship commitment were associated with higher hedonic ratings of a previous partner's BOs, regardless of the type of BOs. For participants currently in a relationship, lower relationship commitment was associated with higher breakup intentions in response to smelling their partner's BOs. These preliminary results contribute evidence for the positive association between exposure to a partner's BOs and favorable hedonic appraisals of BOs; however, further research needs to be conducted in this area to investigate nuances. Lower levels of exposure to one's partner's BOs may be more indicative of relationship commitment than exposure to hedonically unpleasant BOs of one's partner. The findings are discussed with reference to their implications for interventions in relationship breakdown.

Keywords: Sniffin’ sticks; body odor; olfaction; relationship breakdown; romantic relationships.

Title: The self-reported importance of olfaction during human mate choice

Authors: Sergeant, M. J., Davies, M. N., Dickins, T. E., & Griffiths, M. D.

Journal: Sexualities, Evolution & Gender 7.3 (2005): 199-213.

Link to ResearchGate: The self-reported importance of olfaction during human mate choice

Abstract: This study evaluated sex differences in the relative importance placed on olfactory cues during mate choice. To evaluate this, 151 men and 289 women completed an on-line version of the Romantic Interests Survey (RIS) (Herz & Inzlicht, Citation2002). Olfactory characteristics were declared to be extremely important during mate selection, more so than almost all other characteristics, but did not significantly differ between the sexes. There were significant differences concerning the odour source that individuals attend to, with greater preferences observed for a potential mate's body odour as opposed to artificial fragrances they use. These findings suggest the body odour characteristics of a potential mate are perceived to be an important factor during mate choice.

Keywords: Olfactionmate choicesex differencesparental investment

Title: Differential use of sensory information in sexual behavior as a function of gender

Authors: Herz RS, Cahill ED.

Journal: Hum Nat. 1997 Sep;8(3):275-86. doi: 10.1007/BF02912495. PMID: 26196967.

Link to PubMed: Differential use of sensory information in sexual behavior as a function of gender

Abstract: Olfactory information is critical to mammalian sexual behavior. Based on parental investment theory the relative importance of olfaction compared with vision, touch, and hearing should be different for human males and females. In particular, because of its link to immunological profile and offspring viability, odor should be a more important determinant of sexual choice and arousal for females than for males. To test this hypothesis a questionnaire was developed and administered to 332 adults (166 males, 166 females). Subjects used a 1-7 scale to indicate how much they agreed with a series of statements concerning the importance of olfactory, visual, auditory, and tactile information for their sexual responsivity. The data reveal that males rated visual and olfactory information as being equally important for selecting a lover, while females considered olfactory information to be the single most important variable in mate choice. Additionally, when considering sexual activity, females singled out body odor from all other sensory experiences as most able to negatively affect desire, while males regarded odors as much more neutral stimuli for sexual arousal. The present results support recent findings in mice and humans concerning the relation of female preferences in body odor and major histocompatibility complex (MHC) compatibility and can be explained by an evolutionary analysis of sex differences in reproductive strategies. This work represents the first direct examination of the role of different forms of sensory information in human sexual behavior.

Keywords: Evolutionary principles; Gender differences; Odor; Sensory information; Sexual behavior.

Title: Sex differences in response to physical and social factors involved in human mate selection: The importance of smell for women

Authors: Rachel S. Herz, Michael Inzlicht.

Journal: Evolution and Human Behavior, 23(5), 359-364.

Link to ScienceDirect: Sex differences in response to physical and social factors involved in human mate selection: The importance of smell for women

Abstract: A survey study examining the relative importance of various social and physical traits in heterosexual attraction was conducted. Data from 198 male and female heterosexual college students revealed that women ranked body odor as more important for attraction than “looks” or any social factor except “pleasantness.” Moreover, in contrast to response to fragrance use, liking someone's natural body odor was the most influential olfactory variable for sexual interest for both men and women. Men rated a woman's good looks as most desirable and as more important than any other factor except pleasantness. Sex differences in the relative ranking of several social factors were consistent with prior research.